Question

Miguel and Grace started collecting rare coins at the same time. Back then, they had the same number of rare coins. Miguel has been collecting 5 coins each week and he now has 38 coins. Grace has been collecting 3 coins each week and she now has 24 coins. How many rare coins did they have all together when they started collecting?

A) 3
B) 6
C) 7
D) 14

Answer 1

A

3,6,9,12,1518,21,24

5,10,15,20,25,30,35

we can see that there is 3 left when you subtract from 38 by 35. And 3 is a multiple of 3.