Printable primary math worksheet for math grades 1 to 6 based on ... - Free Printable

Problem:

The task is to shade the prime numbers in each set of numbers provided in the image. A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself.

Solution Approach:

1. Understand Prime Numbers:
- A prime number is only divisible by 1 and itself.
- Examples: 2, 3, 5, 7, 11, etc.
- Note: 1 is not a prime number.

2. Check Each Number:
- For each number in the grid, determine if it is prime by checking divisibility by numbers less than its square root.
- If a number is divisible by any integer other than 1 and itself, it is not prime.

3. Shade the Prime Numbers:
- Mark or shade the boxes containing prime numbers.

Step-by-Step Analysis:

#### First Row:
- 71: Prime (divisible only by 1 and 71).
- 169: Not prime (13 × 13 = 169).
- 83: Prime (divisible only by 1 and 83).
- 250: Not prime (even number, divisible by 2).
- 29: Prime (divisible only by 1 and 29).
- 282: Not prime (even number, divisible by 2).
- 293: Prime (divisible only by 1 and 293).

#### Second Row:
- 18: Not prime (even number, divisible by 2).
- 101: Prime (divisible only by 1 and 101).
- 55: Not prime (divisible by 5 and 11).
- 211: Prime (divisible only by 1 and 211).
- 187: Not prime (11 × 17 = 187).
- 125: Not prime (divisible by 5).
- 227: Prime (divisible only by 1 and 227).

#### Third Row:
- 169: Not prime (13 × 13 = 169).
- 229: Prime (divisible only by 1 and 229).
- 113: Prime (divisible only by 1 and 113).
- 73: Prime (divisible only by 1 and 73).
- 257: Prime (divisible only by 1 and 257).
- 81: Not prime (9 × 9 = 81).
- 237: Not prime (divisible by 3).

#### Fourth Row:
- 51: Not prime (3 × 17 = 51).
- 27: Not prime (3 × 9 = 27).
- 97: Prime (divisible only by 1 and 97).
- 281: Prime (divisible only by 1 and 281).
- 230: Not prime (even number, divisible by 2).
- 241: Prime (divisible only by 1 and 241).
- 195: Not prime (divisible by 3 and 5).

#### Fifth Row:
- 283: Prime (divisible only by 1 and 283).
- 299: Not prime (13 × 23 = 299).
- 173: Prime (divisible only by 1 and 173).
- 151: Prime (divisible only by 1 and 151).
- 163: Prime (divisible only by 1 and 163).
- 181: Prime (divisible only by 1 and 181).
- 197: Prime (divisible only by 1 and 197).

#### Sixth Row:
- 17: Prime (divisible only by 1 and 17).
- 89: Prime (divisible only by 1 and 89).
- 67: Prime (divisible only by 1 and 67).
- 279: Not prime (divisible by 3).
- 19: Prime (divisible only by 1 and 19).
- 77: Not prime (7 × 11 = 77).
- 242: Not prime (even number, divisible by 2).

Final Answer:

The prime numbers to be shaded are:
- First Row: 71, 83, 29, 293
- Second Row: 101, 211, 227
- Third Row: 229, 113, 73, 257
- Fourth Row: 97, 281, 241
- Fifth Row: 283, 173, 151, 163, 181, 197
- Sixth Row: 17, 89, 67, 19

Boxed Answer:
\[
\boxed{71, 83, 29, 293, 101, 211, 227, 229, 113, 73, 257, 97, 281, 241, 283, 173, 151, 163, 181, 197, 17, 89, 67, 19}
\]