Ricky collected 3 times as many wind-up toys as Nathan. When Ricky gave Nathan some of his wind-up toys, they each had 8. How many wind-up toys had Ricky given to Nathan?
Nathan starts with N toys
Which means that Ricky starts with 3N toys
3N-k = 8 N+k=8
Solve simultaneously.
1. Put it in a equation: 3n-x = n+x=8
2. Add them up:4n = 16 <=> n =4 Add x to both sides : 3n = n+2x <=> 2x=2n x =n 3. Since x=n and n=4 we have the answer: x=4
