Answer:
8.9 seconds
Explanation:
When caroline catches sam after some time lets say t
distance moved by Caroline will be 80 feet more than sam as they were 80 feet apart.
Given
Let the time taken by Caroline to catch sam is t seconds
distance covered by Caroline in t seconds = speed of caroline*t
distance covered by Caroline in t seconds = 31 * t
distance covered by Caroline in t seconds = 31t feet
distance covered by sam in t seconds = speed of sam*t
distance covered by sam in t seconds = 22 * t
distance covered by sam in t seconds = 22t feet
distance moved by Caroline will be 80 feet more than sam as they were 80 feet apart and caroline catches her in t seconds
thus,
distance covered by Caroline in t seconds = distance covered by sam in t seconds + 80 feet
31t = 22t + 80
subtracting 22t from both sides
=> 31t - 22 t = 80
=> 9t = 80
=>t = 80/9 = 8.9 seconds
Thus,
it will take 8.9 seconds for Caroline to catch Sam