Safety regulations require that the time between airplane takeoffs (on the same runway) will be at least 3 minutes. when taking off, the run time of an airplane on the runway is 39 seconds. planes are on average waiting 5 minutes and 33 seconds for take-off. on average there are 15 planes taking off per hour. how many planes are either on the runway or waiting to take off?

1 plane.

Step-by-step explanation:

Let's call the number of planes waiting or on the runway of WIP, the number of planes taking off per hour of TR, and the time for waiting and the runway of TT, so:

WIP = TRxTT

TR = 18 airplanes per hour

Knowing that 1 min = 60s ⇒ 39s = 39/60 = 0.65 min, and 5 min and 33s = 5 + 33/60 = 5.55 min

TT = 0.65 + 5.55 = 6.2 min/60 = 0.1033 h

WIP = 15x0.1033 = 1.55

So, there is 1 plane either on the runway or waiting to take off

proportions are fractions that equal to each other. so if two fractions are the same, they are proportional.

let's check the answers to see if they are proportional.

question a is not proportional because you can't turn 1.5/3 to 3/9. if you try to multiply 1.5/3 by 2 or 3, you wont get 3/9. it's impossible to make the fractions the same.

question b is not proportional because you can't turn 22/33 to 4/6. 33 can't go into 6.

question c is proportional because when you multiply 2 and 3 by 71, you would get 142/213, and those fractions equal to each other

question d is proportional because when you divide 14 and 7 by 2, you would end up with 7/3.5, and those fractions equal to each other.

answer: can you show the options ?

step-by-step explanation: