1.) 7 to 9 yes, that is simplest form because, he cannot divide or multiply.

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2.) 10 to 16 no, because, you can still divide him.

10 ÷ 2 = 5

16 ÷ 2 = 8

5 to 8 that is the simplest form of 10 to 16.

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3.) 13 to 17 yes, because that's his simplest form and it's done divide or mulitply

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4.) 6 to 8 no, because you can divide him.

6 ÷ 2 = 3

8 ÷ 2 = 4

3 to 4 that is the simplest form of 6 to 8.

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5.) 21 to 24 no, because you can Divide him.

21 ÷ 3 = 7

24 ÷ 3 = 8

7 to 8 that is the simplest form of 21 to 24.

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6.) 5 to 6 yes, because that he divide or that multiply.

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7.) 8 to 24 no, because you can Divide him.

8 ÷ 8 = 1

24 ÷ 8 = 3

1 to 3 that is the simplest form of 8 to 24.

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8.) 3 to 15, no, because you can Divide him.

3 ÷ 3 = 1

15 ÷ 3 = 5

1 to 5 that is the simplest form of 3 to 15.

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9.) 22 to 23 yes, because that he divide or that multiply.

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10.) 20 to 30 no, because you can Divide him.

20 ÷ 10 = 2

30 ÷ 10 = 3

2 to 3 that is the simplest form of 20 to 30.