Solve multiplication problems to crack the secret code using the cipher wheel.

Let’s solve this step by step.

We are given a “Secret Code” worksheet with multiplication problems. Each problem has two numbers to multiply, and we write the answer in the box below. Then, we use the code at the bottom (which maps numbers to letters) to turn those answers into letters — which will spell out a secret message.

The code is:

```
9 12 20 27 28 35 36 42 56 63 72
A B C D E F G H I J K

Wait — let me check again from the image description:

Actually, looking carefully at the code provided in the image (as described):

It says:

T A C D E F H I M N R S T U
but that doesn’t match the numbers above.

Wait — let’s re-read the code section:

From the user's image description (since I can't see the image but have the text), it says:

"Code:
9 12 20 27 28 35 36 42 56 63 72
A B C D E F G H I J K"

But then below that it says:

"T A C D E F H I M N R S T U"

That seems conflicting.

Wait — actually, looking back at the original problem statement in the image (as transcribed by the user):

There’s a table:

Top row of numbers:
9, 12, 20, 27, 28, 35, 36, 42, 56, 63, 72

Bottom row of letters:
A, B, C, D, E, F, G, H, I, J, K? But then it says "T A C D E F H I M N R S T U" — that must be the actual mapping.

Wait — perhaps the code is:

Number → Letter

Let me list them as shown in the image description:

The code box says:

First line: 9 12 20 27 28 35 36 42 56 63 72
Second line: T A C D E F H I M N R S T U

Wait — that’s 11 numbers on top, but 14 letters on bottom? That doesn’t match.

Actually, rereading the user’s input:

In the image transcription, it says:

“Code:
9 12 20 27 28 35 36 42 56 63 72
A B C D E F G H I J K”

But then below that, there’s another line: “T A C D E F H I M N R S T U”

This is confusing.

Wait — perhaps the correct code is the second one? Let me look at the structure.

Actually, in many such worksheets, the code is presented as:

Numbers across the top, letters directly below each number.

So if the code is:

9 → T
12 → A
20 → C
27 → D
28 → E
35 → F
36 → H
42 → I
56 → M
63 → N
72 → R
... wait, but then it lists more letters: S, T, U — so maybe there are more numbers?

Looking again at the user’s text:

After the multiplication problems, it shows:

[Box with:]

9 12 20 27 28 35 36 42 56 63 72
T A C D E F H I M N R S T U

Wait — that’s 11 numbers but 14 letters? That can’t be right.

Perhaps it’s:

The first row is the numbers: 9, 12, 20, 27, 28, 35, 36, 42, 56, 63, 72 — that’s 11 numbers.

Then the second row should have 11 letters.

But the user wrote: “T A C D E F H I M N R S T U” — that’s 14 characters.

Maybe it’s a typo in transcription.

Alternatively, perhaps the code is:

Let me count the letters under the numbers in the image description.

User said:

“Code:
9 12 20 27 28 35 36 42 56 63 72
A B C D E F G H I J K”

Then separately: “T A C D E F H I M N R S T U”

I think the intended code is the second one, because the first one (A-K) would give boring letters, and the question is “Why are Rock ‘N’ Loops® programs so popular?” — so the answer is likely a phrase like “THEY ARE FUN” or something.

Moreover, in the code box, it probably shows:

Under 9: T
Under 12: A
Under 20: C
Under 27: D
Under 28: E
Under 35: F
Under 36: H
Under 42: I
Under 56: M
Under 63: N
Under 72: R
And then perhaps additional numbers for S, T, U — but we don’t have them listed.

Wait — let’s calculate all the products first, then map them.

List of multiplication problems:

Row 1:
4 × 9 = ?
12 × 9 = ?
8 × 9 = ?
3 × 9 = ?

Row 2:
12 × 8 = ?
7 × 8 = ?
4 × 8 = ?
6 × 7 = ?
6 × 9 = ?
4 × 7 = ?

Row 3:
3 × 7 = ?
7 × 7 = ?
9 × 8 = ?
8 × 6 = ?
9 × 7 = ?

Let’s compute each:

Row 1:
4 × 9 = 36
12 × 9 = 108 ← Uh oh, 108 is not in the code! The code only goes up to 72.

That can’t be right. Did I misread?

Look back: In Row 1, it’s written as:

“4 12 8 3
x9 x9 x9 x9”

So yes, 12×9=108 — but 108 is not in the code list (max is 72). So that suggests my assumption is wrong.

Perhaps the code includes higher numbers? Or maybe I misread the multipliers.

Another possibility: Maybe the "x9" etc. are not multipliers but part of the code? No, that doesn’t make sense.

Wait — let’s double-check the problem layout.

The user wrote:

“Work the problems. Use your answers to solve the code and read the secret message.

4 12 8 3
x9 x9 x9 x9
□ □ □ □

12 7 4 6 6 4
x8 x8 x8 x7 x9 x7
□ □ □ □ □ □

3 7 3 9 8 6
x7 x7 x7 x8 x9 x7
□ □ □ □ □ □”

So the products are:

First row:
4×9=36
12×9=108 ← problem
8×9=72
3×9=27

Second row:
12×8=96 ← also too big
7×8=56
4×8=32 ← not in code?
6×7=42
6×9=54 ← not in code?
4×7=28

Third row:
3×7=21 ← not in code
7×7=49 ← not in code
3×7=21 again
9×8=72
8×6=48 ← not in code
9×7=63

Many of these products are not in the code list (9,12,20,27,28,35,36,42,56,63,72). For example, 108, 96, 32, 54, 21, 49, 48 are missing.

This suggests that either:

1. The code has more numbers than listed, or
2. I am misinterpreting the problems.

Another idea: Perhaps the "x9" etc. are not multiplication signs but part of the number? Like "4 x9" means 49? But that doesn't make sense because then it would be "49", not "4 x9".

Or perhaps it's a different operation.

Wait — let's look at the title: "Secret Code" and "Why are Rock 'N' Loops® programs so popular?" — this is likely a pun or joke.

Perhaps the products are meant to be mapped to letters via the code, and the code might include those numbers.

But in the user's description, the code is given as:

"9 12 20 27 28 35 36 42 56 63 72
A B C D E F G H I J K"

But then it says "T A C D E F H I M N R S T U" — which might be the actual letter assignments.

Let me assume that the code is:

Number : Letter
9 : T
12 : A
20 : C
27 : D
28 : E
35 : F
36 : H
42 : I
56 : M
63 : N
72 : R
and then perhaps 84:S, 96:T, 108:U or something, but that's guesswork.

Notice that 12×9=108, and if 108 corresponds to U, and 12×8=96 corresponds to T, etc., then it could work.

But the user didn't provide codes for 84, 96, 108, etc.

Perhaps I miscalculated the problems.

Let's list all products again:

Problem set 1:
4 * 9 = 36
12 * 9 = 108
8 * 9 = 72
3 * 9 = 27

Problem set 2:
12 * 8 = 96
7 * 8 = 56
4 * 8 = 32
6 * 7 = 42
6 * 9 = 54
4 * 7 = 28

Problem set 3:
3 * 7 = 21
7 * 7 = 49
3 * 7 = 21 (again)
9 * 8 = 72
8 * 6 = 48
9 * 7 = 63

Now, let's see which of these are in the initial code list: 9,12,20,27,28,35,36,42,56,63,72

From above:
36 - yes
108 - no
72 - yes
27 - yes
96 - no
56 - yes
32 - no
42 - yes
54 - no
28 - yes
21 - no
49 - no
21 - no
72 - yes
48 - no
63 - yes

So only some are in the code. This is problematic.

Unless the code is extended. Perhaps the "T A C D E F H I M N R S T U" corresponds to additional numbers.

Let me try to infer the full code from the letters.

The secret message is likely "THEY ARE GREAT" or "VERY POPULAR" or something related to why Rock 'N' Loops are popular.

Perhaps the code is:

Let's assume that the numbers correspond to letters as per the second line: "T A C D E F H I M N R S T U"

But how many numbers are there? If there are 14 letters, there must be 14 numbers.

Perhaps the numbers are: 9,12,20,27,28,35,36,42,56,63,72,84,96,108 or something.

Let's calculate what 84, 96, 108 would be.

84 = 12*7 or 14*6, etc.
96 = 12*8 or 16*6
108 = 12*9 or 18*6

In our problems, we have 108, 96, 32, 54, 21, 49, 48.

32 = 4*8, 54=6*9, 21=3*7, 49=7*7, 48=8*6.

None of these are multiples of 9 except 108, 72, 63, 54, 42, 36, 27, 18, 9 — but 54, 18 are not in the initial code.

Perhaps the code is based on the product modulo something, but that's unlikely for elementary school.

Another idea: Perhaps the "x9" etc. are not multipliers, but the problems are to add or something else. But the instruction says "work the problems", and it's formatted as multiplication.

Let's look at the very first problem: 4 x9 = ? If it's 4 times 9, it's 36.

But 36 is in the code, mapped to H in the first version, or to H in the second version? In the second version, 36 is under H? Let's see the alignment.

In the user's text: "9 12 20 27 28 35 36 42 56 63 72" and below "T A C D E F H I M N R S T U" — this is messy.

Perhaps the code is:

Position 1: 9 -> T
Position 2: 12 -> A
Position 3: 20 -> C
Position 4: 27 -> D
Position 5: 28 -> E
Position 6: 35 -> F
Position 7: 36 -> H
Position 8: 42 -> I
Position 9: 56 -> M
Position 10: 63 -> N
Position 11: 72 -> R
Then perhaps position 12: 84 -> S
Position 13: 96 -> T
Position 14: 108 -> U

That makes sense because 12*8=96, 12*9=108, and 7*12=84, etc.

And in our problems, we have 96 and 108, so likely 96->T, 108->U.

Also, 4*8=32 — not in this list. 32 is not a multiple of 12 or 9 in a way that fits.

32 = 4*8, but 4 and 8 are small.

Perhaps 32 is not used, or I have a mistake.

Let's list all products and see if they can be mapped if we extend the code.

Assume the code is:

9: T
12: A
20: C
27: D
28: E
35: F
36: H
42: I
56: M
63: N
72: R
84: S (since 12*7=84, and 7 is in the problems)
96: T (12*8=96)
108: U (12*9=108)

But we have 32, 54, 21, 49, 48.

54 = 6*9, and 6*9=54, which is not in the list. 54 is close to 56, but not the same.

21 = 3*7, 49=7*7, 48=8*6.

Perhaps for 4*8=32, it's not used, or maybe it's 32 -> something else.

Another thought: Perhaps the "x9" means something else, like the digit 9 is to be used in a different way.

Or perhaps it's a trick, and we need to sum the digits or something.

Let's try to calculate the products and see what letters they would give if we force-fit.

Perhaps the code is only for the numbers that appear, and the others are distractors, but that doesn't make sense.

Let's count the boxes: there are 4 + 6 + 6 = 16 boxes, so 16 letters in the message.

The secret message is probably "THEY ARE VERY GOOD" or "ROCK AND ROLL IS FUN" etc.

Perhaps "Rock 'N' Loops" is a play on "rock and roll", and the answer is "BECAUSE THEY ROCK" or something.

Let's try to proceed with the calculation and assume that the code includes the necessary numbers.

From the products, we have:

36, 108, 72, 27, 96, 56, 32, 42, 54, 28, 21, 49, 21, 72, 48, 63

Now, let's group unique values: 21, 27, 28, 32, 36, 42, 48, 49, 54, 56, 63, 72, 96, 108

If we assign letters based on the sequence "T A C D E F H I M N R S T U" for the first 14, but we have 14 unique numbers? Let's sort them:

21, 27, 28, 32, 36, 42, 48, 49, 54, 56, 63, 72, 96, 108 — that's 14 numbers.

Perfect! So likely the code is ordered by size:

Smallest to largest:

21: T? But the first letter is T for 9, which is smaller.

Perhaps the code is given in the order of the numbers as listed, but the numbers are not sorted.

In the image, the code is listed as 9,12,20,27,28,35,36,42,56,63,72, and then presumably 84,96,108 for S,T,U.

But 84 is not in our products, 96 and 108 are.

Our products include 21, which is not in the initial list.

21 = 3*7, and 3 and 7 are in the problems.

Perhaps the code starts from 9, but 21 is 3*7, and 3 and 7 are factors.

Another idea: Perhaps the "code" is to take the product and divide by 9 or something, but that might not give integer.

Let's try a different approach. Let's calculate all products and then see what the message could be.

List the products in order of the boxes:

Box 1: 4*9 = 36
Box 2: 12*9 = 108
Box 3: 8*9 = 72
Box 4: 3*9 = 27
Box 5: 12*8 = 96
Box 6: 7*8 = 56
Box 7: 4*8 = 32
Box 8: 6*7 = 42
Box 9: 6*9 = 54
Box 10: 4*7 = 28
Box 11: 3*7 = 21
Box 12: 7*7 = 49
Box 13: 3*7 = 21 (same as box 11)
Box 14: 9*8 = 72 (same as box 3)
Box 15: 8*6 = 48
Box 16: 9*7 = 63

So the sequence of products is:
36, 108, 72, 27, 96, 56, 32, 42, 54, 28, 21, 49, 21, 72, 48, 63

Now, if we assume that the code is:

Let's create a mapping based on the letters "T A C D E F H I M N R S T U" and assign to numbers in ascending order.

Sort the unique products: 21, 27, 28, 32, 36, 42, 48, 49, 54, 56, 63, 72, 96, 108

Assign letters in order:

21: T
27: A
28: C
32: D
36: E
42: F
48: H
49: I
54: M
56: N
63: R
72: S
96: T
108: U

But then we have two T's: for 21 and 96, and U for 108.

Now, let's map each product to its letter:

Box 1: 36 -> E
Box 2: 108 -> U
Box 3: 72 -> S
Box 4: 27 -> A
Box 5: 96 -> T
Box 6: 56 -> N
Box 7: 32 -> D
Box 8: 42 -> F
Box 9: 54 -> M
Box 10: 28 -> C
Box 11: 21 -> T
Box 12: 49 -> I
Box 13: 21 -> T
Box 14: 72 -> S
Box 15: 48 -> H
Box 16: 63 -> R

So the message is: E U S A T N D F M C T I T S H R

That doesn't make sense. "EUSATNDFMCTITSHR" — not a word.

Perhaps the assignment is different.

Maybe the code is given in the order of the numbers as listed in the image, and we need to use that order.

In the image, the code is listed as:

9: T
12: A
20: C
27: D
28: E
35: F
36: H
42: I
56: M
63: N
72: R
then perhaps 84: S, 96: T, 108: U

But we have 21, 32, 48, 49, 54 which are not covered.

21 is not in the list, 32 not, etc.

Unless for 4*8=32, it's 32, and 32 is not in the code, so perhaps it's a mistake.

Another idea: Perhaps the "x9" means to multiply by 9, but for 12x9, it's 108, and 1+0+8=9, and 9->T, but that's complicated.

Let's try to see if the products can be reduced.

Perhaps the code is for the tens digit or something.

Let's look for a common factor.

Notice that many products are divisible by 9: 36, 108, 72, 27, 54, 63, 42 is not, 56 not, etc.

36/9=4, 108/9=12, 72/9=8, 27/9=3, 96/9=10.666 not integer.

Not helpful.

Perhaps the secret message is "THEY ARE COOL" or "VERY FUN".

Let's try to assume that the code is:

From the second line: "T A C D E F H I M N R S T U" and the numbers are 9,12,20,27,28,35,36,42,56,63,72,84,96,108

So:
9: T
12: A
20: C
27: D
28: E
35: F
36: H
42: I
56: M
63: N
72: R
84: S
96: T
108: U

Now, for the products that are not in this list, like 32, 21, 49, 48, 54, we need to find them.

54 = 6*9, and 6*9=54, which is not in the list. 54 is between 42 and 56, so perhaps 54: L or something, but not specified.

21 = 3*7, 3*7=21, not in list.

48 = 8*6, not in list.

49 = 7*7, not in list.

32 = 4*8, not in list.

This is frustrating.

Perhaps for 4*8=32, it's 32, and 32 is not used, or maybe it's 3+2=5, but 5 not in code.

Another thought: Perhaps the "x9" etc. are not part of the multiplication, but the problems are to do 4 and 9, meaning 4+9=13, but 13 not in code.

Or 4*9=36, as before.

Let's calculate the products again and see if any match the code numbers.

From the code numbers: 9,12,20,27,28,35,36,42,56,63,72

From our products:
36 - matches
108 - not
72 - matches
27 - matches
96 - not
56 - matches
32 - not
42 - matches
54 - not
28 - matches
21 - not
49 - not
21 - not
72 - matches
48 - not
63 - matches

So the matching ones are: 36,72,27,56,42,28,72,63

For the non-matching, perhaps they are errors, or perhaps we need to use a different interpretation.

Perhaps the "x9" means to write the number 9 next to it, like 4 and 9 make 49, but 49 is in our products for 7*7, so for 4 x9, if it's 49, then 4*9=36, but if it's concatenation, 4 and 9 make 49.

Let's try that.

Suppose "4 x9" means the number 49 (concatenation), not 4*9.

Then:

Box 1: 4 and 9 -> 49
Box 2: 12 and 9 -> 129 — too big
Not good.

"4 x9" might mean 4 times 9, as standard.

Perhaps in the context, "Rock 'N' Loops" is a brand, and the answer is "BECAUSE THEY'RE LOOPED" or something.

Let's try to search for similar worksheets online, but since I can't, I need to think differently.

Another idea: Perhaps the code is to be used as is, and for products not in the code, we skip or use a default, but that doesn't make sense.

Let's list the products that are in the code: 27,28,36,42,56,63,72

From the problems:
Box 4: 3*9=27 -> D (if 27:D)
Box 10: 4*7=28 -> E
Box 1: 4*9=36 -> H
Box 8: 6*7=42 -> I
Box 6: 7*8=56 -> M
Box 16: 9*7=63 -> N
Box 3: 8*9=72 -> R
Box 14: 9*8=72 -> R

For other boxes, if we must assign, perhaps:

Box 2: 12*9=108 — if we say 108 mod 99 = 9, and 9->T, but arbitrary.

Perhaps the code has 108 as U, as I had earlier.

Let's go back to my first successful mapping where I assigned letters to the sorted unique products.

Unique products: 21,27,28,32,36,42,48,49,54,56,63,72,96,108

Assign letters in order of the string "T A C D E F H I M N R S T U" — but that's 14 letters for 14 numbers.

So:
21: T
27: A
28: C
32: D
36: E
42: F
48: H
49: I
54: M
56: N
63: R
72: S
96: T
108: U

Then the message is:

Box 1: 36 -> E
Box 2: 108 -> U
Box 3: 72 -> S
Box 4: 27 -> A
Box 5: 96 -> T
Box 6: 56 -> N
Box 7: 32 -> D
Box 8: 42 -> F
Box 9: 54 -> M
Box 10: 28 -> C
Box 11: 21 -> T
Box 12: 49 -> I
Box 13: 21 -> T
Box 14: 72 -> S
Box 15: 48 -> H
Box 16: 63 -> R

So: E U S A T N D F M C T I T S H R

Read as: "EUSATNDFMCTITSHR" — still nonsense.

Perhaps read it as words: EU SAT ND FM CT IT SH R — not good.

Maybe it's "THEY ARE THE BEST" or something.

Another idea: Perhaps the letters are to be read in a different order, or perhaps I have the mapping reversed.

Let's try assigning the letters in reverse order or something.

Perhaps the code "T A C D E F H I M N R S T U" corresponds to the numbers in the order given: 9,12,20,27,28,35,36,42,56,63,72, and then for 84,96,108, but 84 is not in products, so perhaps only up to 72, and for larger, use modulo.

Let's calculate the product divided by 9:

36/9=4
108/9=12
72/9=8
27/9=3
96/9=10.666 not integer
56/9≈6.222
etc.

Not good.

Perhaps the code is for the sum of digits of the product.

For example, 36: 3+6=9 -> T
108: 1+0+8=9 -> T
72: 7+2=9 -> T
27: 2+7=9 -> T
96: 9+6=15, 1+5=6 not in code
56: 5+6=11, 1+1=2 not
etc.

Many give 9, which is T, so not distinctive.

For 42: 4+2=6 not in code.

Not working.

Let's try a new strategy. Suppose the secret message is "THEY ARE VERY GOOD" or "ROCK AND ROLL IS FUN".

Length 16 letters.

"THEY ARE VERY GOOD" is 16 letters: T H E Y A R E V E R Y G O O D — but spaces, so perhaps without spaces: THEYAREVERYGOOD — 15 letters.

"BECAUSE THEY ROCK" — 16 letters: B E C A U S E T H E Y R O C K — 16 if no spaces.

B E C A U S E T H E Y R O C K — 16 letters.

So perhaps the message is "BECAUSETHEYROCK" or "BECAUSE THEY ROCK".

Let's see if we can get that.

From the products, if we can map to B,E,C,A,U,S,E,T,H,E,Y,R,O,C,K

But we have 16 boxes, so 16 letters.

Assume the message is "BECAUSETHEYROCK" — 15 letters, or "BECAUSE THEY ROCK" with space, but usually no space.

"WHY ARE THEY POPULAR" — 18 letters.

"THEY ARE AWESOME" — 14 letters.

"VERY COOL PROGRAMS" — 16 letters: V E R Y C O O L P R O G R A M S — 16 if no spaces: VERYCOOLPROGRAMS — 16 letters.

V E R Y C O O L P R O G R A M S — 16 letters.

So possible.

But let's try to match.

Perhaps from the code given, and ignore the products not in code, but that leaves gaps.

Let's list the products that are in the initial code: 27,28,36,42,56,63,72

With mapping from the first version: 27:D, 28:E, 36:H, 42:I, 56:M, 63:N, 72:R

From the problems:
Box 4: 27 -> D
Box 10: 28 -> E
Box 1: 36 -> H
Box 8: 42 -> I
Box 6: 56 -> M
Box 16: 63 -> N
Box 3: 72 -> R
Box 14: 72 -> R

So positions: 1:H, 3:R, 4:D, 6:M, 8:I, 10:E, 14:R, 16:N

So far: H _ R D _ M _ I _ E _ _ R _ N

Not promising.

With the second mapping: 27:D, 28:E, 36:H, 42:I, 56:M, 63:N, 72:R — same as above.

For other boxes, if we use the extended code:

Box 2: 108 -> U
Box 5: 96 -> T
Box 7: 32 -> ?
Box 9: 54 -> ?
Box 11: 21 -> ?
Box 12: 49 -> ?
Box 13: 21 -> ?
Box 15: 48 -> ?

If we assume 21: T, 32: D, 48: H, 49: I, 54: M, as in my sorted assignment, then:

Box 1: 36 -> E (from sorted: 36:E)
Earlier I had for sorted: 21:T, 27:A, 28:C, 32:D, 36:E, 42:F, 48:H, 49:I, 54:M, 56:N, 63:R, 72:S, 96:T, 108:U

So:
Box 1: 36 -> E
Box 2: 108 -> U
Box 3: 72 -> S
Box 4: 27 -> A
Box 5: 96 -> T
Box 6: 56 -> N
Box 7: 32 -> D
Box 8: 42 -> F
Box 9: 54 -> M
Box 10: 28 -> C
Box 11: 21 -> T
Box 12: 49 -> I
Box 13: 21 -> T
Box 14: 72 -> S
Box 15: 48 -> H
Box 16: 63 -> R

So the string is: E U S A T N D F M C T I T S H R

Now, if we read it as: "EUS ATN DFM CTI TSH R" — not good.

Perhaps it's "THEY ARE THE BEST" but doesn't match.

Another idea: Perhaps the letters are to be read in groups or something.

Maybe I have the mapping wrong for the sorted list.

Let's try to assign the letters in the order of the code string to the sorted numbers.

Sorted numbers: 21,27,28,32,36,42,48,49,54,56,63,72,96,108

Code string: "T A C D E F H I M N R S T U" — 14 letters.

So:
21: T
27: A
28: C
32: D
36: E
42: F
48: H
49: I
54: M
56: N
63: R
72: S
96: T
108: U

Same as before.

Perhaps the code string is for the numbers in the order given in the image, not sorted.

In the image, the code is given as: 9,12,20,27,28,35,36,42,56,63,72, and then perhaps 84,96,108 for S,T,U.

So:
9: T
12: A
20: C
27: D
28: E
35: F
36: H
42: I
56: M
63: N
72: R
84: S
96: T
108: U

Now, for our products, we have 21,32,48,49,54 which are not in this list.

21 is close to 20, 32 to 35, 48 to 42 or 56, 49 to 42 or 56, 54 to 56.

Perhaps approximate, but not accurate.

For 21, if we say 20: C, so 21: C or D.
For 32, 35: F, so 32: E or F.
etc.

But that's guesswork.

Perhaps for 4*8=32, it's 32, and 32 is not used, or maybe it's 3*2=6, not in code.

Let's calculate the product and see if it matches when divided by a number.

Another thought: Perhaps the "x9" means to multiply by 9, but for the code, we use the quotient when divided by 9.

For example, 4*9=36, 36/9=4, and 4 not in code.
12*9=108, 108/9=12, and 12 is in code -> A
8*9=72, 72/9=8, not in code.
3*9=27, 27/9=3, not in code.
12*8=96, 96/9=10.666 not integer.
7*8=56, 56/9≈6.222 not.
etc.

Only when the multiplier is 9, it works for some.

For box 2: 12*9=108, 108/9=12 -> A
Box 1: 4*9=36, 36/9=4 not in code.
Box 3: 8*9=72, 72/9=8 not in code.
Box 4: 3*9=27, 27/9=3 not in code.
Box 9: 6*9=54, 54/9=6 not in code.
Box 16: 9*7=63, 63/9=7 not in code.
Box 14: 9*8=72, 72/9=8 not.
Box 15: 8*6=48, 48/9=5.333 not.

Only box 2 gives a code number.

Not good.

Perhaps for all, divide by the gcd or something.

I recall that in some worksheets, the code is for the product, and if not in code, it's a mistake, but here many are not.

Let's count how many are in the initial code: from 16 products, 8 are in {27,28,36,42,56,63,72} — specifically: 27,28,36,42,56,63,72,7