Answer:
3 hours
Step-by-step explanation:
Speed is the ratio of distance traveled to time taken, it is given as:
Speed = distance / time
An executive drove from his home at an average speed of 35 mph to an airport where a helicopter was waiting. He then took the helicopter and flew to the corporate offices at an average speed of 78 mph. Given that the executive spent the same amount of time in the car as he did the helicopter how long did it take the executive to get to work.
Let the amount of time the executive spent in the car be t hours, therefore the amount of time spent in the helicopter = t hours.
For car:
Speed = distance / time
35 = distance ([tex]d_1[/tex]) / t
[tex]d_1=35t[/tex]
For helicopter:
Speed = distance / time
78 = distance ([tex]d_2[/tex]) / t
[tex]d_2=78t[/tex]
The total distance traveled = 169.5 miles
[tex]d_1+d_2=169.5\\35t+78t=169.5\\113t=169.5\\t=169.5/113\\t=1.5\ hours[/tex]
The time taken for the executive to get to work = time spent on car + time spent on helicopter = 1.5 + 1.5 = 3 hours
