Explanation:
We are given six problems (a–f). Each shows blocks grouped into
tens (vertical rods of 10 blocks) and
ones (single blocks). We need to:
1. Count how many tens (T) there are → that’s the number of rods × 10.
2. Count how many ones (O) there are → just count the single blocks.
3. Write the sum as: T + O = total.
Let’s go one by one.
---
a)
- Tens: 2 rods → 2 × 10 =
20
- Ones: top row has 4 singles, bottom row has 3 singles → 4 + 3 =
7
- So: 20 + 7 =
27
---
b)
- Tens: 4 rods → 4 × 10 =
40
- Ones: top row 3 singles, bottom row 2 singles → 3 + 2 =
5
- So: 40 + 5 =
45
---
c)
- Tens: 4 rods → 4 × 10 =
40
- Ones: top row 2, bottom row 2 → 2 + 2 =
4
- So: 40 + 4 =
44
---
d)
- Tens: 5 rods → 5 × 10 =
50
- Ones: top row 3, middle row 3, bottom row 2 → 3 + 3 + 2 =
8
- So: 50 + 8 =
58
---
e)
- Tens: 4 rods → 4 × 10 =
40
- Ones: only 1 single block
- So: 40 + 1 =
41
---
f)
- Tens: 3 rods → 3 × 10 =
30
- Ones: top row 4, middle row 4, bottom row 1 → 4 + 4 + 1 =
9
- So: 30 + 9 =
39
Double-check all counts:
- a: 2 rods + 7 singles = 27
✔
- b: 4 rods + 5 singles = 45
✔
- c: 4 rods + 4 singles = 44
✔
- d: 5 rods + 8 singles = 58
✔
- e: 4 rods + 1 single = 41
✔
- f: 3 rods + 9 singles = 39
✔
All correct.
Final Answer:
a) 20 + 7 = 27
b) 40 + 5 = 45
c) 40 + 4 = 44
d) 50 + 8 = 58
e) 40 + 1 = 41
f) 30 + 9 = 39
Parent Tip: Review the logic above to help your child master the concept of place value blocks worksheet 3rd grade.
