Adam and Hunter each had a collection of seashells. The ratio of Adam's seashells to Hunter's seashells was 2:1. When Hunter found 15 more seashells, the ratio became 1:2. How many seashells did Adam have?
Let Hunter's seashells be H
Then Adam has 2H
When Hunter finds 15 more we have that he now has twice as many as Adam....so....
H + 15 = 2 ( 2H) simplify
H + 15 = 4H
15 = 4H -H
15 = 3H
15 / 3 = H = 5
Adam had 2H = 2 (5) = 10 shells
