Question 56574
A cheeta is 300 ft. from its prey.It starts to sprint towards its prey at 90 ft. per second. At the same time, thee prey starts to sprint at 70 ft. per second. When will the cheeta catch its prey?

Let d = distance the prey travel when it is caught
Then (d + 300) = distance the cheetah travels when it catches
:
Both animals will be traveling for same number of seconds
Write time equation: t = dist/speed
:
Cheetah's time = Prey's time
     {{{(d+300)/90}}} = {{{d/70}}}
:
Cross mult:
70(d+300) = 90d
70d + 21000 = 90d
21000 = 90d - 70d
  20d = 21000
    d = 21000/20
    d = 1050 ft traveled by the unfortunate one
:
and 1350 ft traveled by the hungry one:
:
Time = 1350/90 = 15 sec
:
Check: 1050/70 = 15 sec also