Answer:
Ben has 225 seashells
Step-by-step explanation:
Step 1: Use the ratio to see how many times the amount Andy has
4 * n = 100
4n / 4 = 100 / 4
n = 25 times the amount of the ratio
Step 2: Find out how many shells Ben has
Use the 25 times the ratio to help
9 * 25
225
Answer: Ben has 225 seashells
Check: See if the ratio still works
Andy = 100
Ben = 225
100 : 225
(100/25) : (225/25)
4 : 9 -> Correct, so the answer is good