this is my word problem, Sharon has less than 20 coins. When she puts them in piles of 5, she has 1 left over. When she put them in piles of 3, she also has 1 left over. How many coins does Sharon have? (Show how you find your solution).

I have one more I don't understand, Sylvia has less than 40 coins but more than 10. If she puts them in piles of 6, she has 3 left over. If she puts them in piles of 5, she has 4 left over. How many coins does Sylvia have?

Hi,

"When she puts them in piles of 5, she has 1 left over." Another way to say this is that if she divided the number of coins she has by 5 she gets a remainder of 1. So what are the possibilities?

6, 11, 16 (These numbers are 5 + 1, 2x5 + 1 and 3x5 + 1)

"When she put them in piles of 3, she also has 1 left over." So the possibilities here are

4, 7, 10, 13, 16, 19 (3 + 1, 2x3 + 1, 3x3 + 1, ...)

The only number in both lists is 16.

Can you do the second problem now?
Penny

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