Answer:
Correct answer: t = 10 seconds
Step-by-step explanation:
Given:
V₁ = 12 ft/s , V₂ = 10 ft/s initial distance d = 20 ft
To the moment he catches his friend the first skater will have crossed the distance d₁ and the second d₂.
d₁ = d + d₂
d₁ = V₁ · t
d₂ = V₂ · t
when we substitute this into the initial formula we get:
V₁ · t = d + V₂ · t ⇒ d = V₁ · t - V₂ · t ⇒ d = t (V₁ - V₂) ⇒ t = d / (V₁ - V₂)
t = d / (V₁ - V₂) = 20 / (12 - 10) = 20 / 2 = 10 seconds
t = 10 seconds
God is with you!!!