Bunuel wrote:
A certain CEO drove from his home to a helipad at an average rate of 50 miles per hour and then boarded a helicopter, which traveled at an average speed of 80 miles per hour, to his office building. If it took the CEO 1.5 hours to reach his office building from home and he spent 4 times as long driving as he did flying, what is the distance from his home to his office building?
A. 84
B. 75
C. 72
D. 60
E. 18
total time =1.5 hrs = 90 minutes
let time taken to cover helipad to office=x minutes
then time taken from home to helipad =4x
thus 4x+x=90
5x=90
x=18minutes
4x =72 mnutes
distance = speed*time
distance of home to helipad = 50*72/60 = 60miles
distance of helipad to office = 80*18/60 = 24miles
thus total distance = 60+24=84miles
Ans A