Chris and Josh have received walkie-talkies for Christmas. If they leave from the same point at the same time, Chris walking north at 2.5 mph and Josh walking east at 3 mph, how long will they be able to tlak to each other if the range of the walkie talkies is 4 miles? Round your answer to the nearest minute.
The distance between them is the hypotenuse of a right triangle. The legs of the triangle are the distances that they travel:
Chris: Y = 2.5 t
Josh: X = 3.0 t, if t is in hours and X and Y are in miles.
When they are 4 miles apart
4^2 = X^2 + Y^2 = [(2.5)^2 + (3.0^2] ^2
16 = 15.25 t^2
t^2 = 1.049 hr^2
t = 1.024 hours = 61 minutes
4 answers