Answer:
200 ft 200
t = -------------------- = ---------- min
(S + T) ft/min S + T
Step-by-step explanation:
Recall that distance = (rate)(time).
The distance traveled by the turtle in t minutes is dt = (T ft/min)(t), and
the distance traveled by the snail in t minutes is ds = (S ft/min)(t). We know that ds + dt must be 200 ft.
Thus,
(S ft/min)(t) + (T ft/min)(t) = 200 ft.
The variable t, representing elapsed time, is common to both terms on the left. Thus,
200 ft 200
t = -------------------- = ---------- min
(S + T) ft/min S + T
