Finding the distance

Question

An executive drove from home at an average speed of 45 mph to an airport where a helicopter was waiting. The executive boarded the helicopter and flew to the corporate offices at an average speed of 60 mph. The entire distance was 170 mi. The entire trip took 3 h. Find the distance from the airport to the corporate offices. 

Answer 1

total distance = 170 miles

total time  = 3 hrs

suppose time taken to travel from Airport to corporate office  = x hour

then time taken to travel from home to airport  = (3 -x) hour  [ because total time is 3 hr]

 

we know,  distance = speed * time

 

total distance  = distance from Airport to corporate office + distance from home to airport

170  miles =     60 * x       +  45 * (3-x)

170 = 60x + 135 - 45 x

170 = 15 x + 135

170-135 = 15 x

35/ 15   hour = x

so, 

the distance between Airport to corporate office is then      (35/15)*60 =  140 miles.