11. An airplane flying against the wind travels 140 miles in the same amount of time it would take the same plane to travel 160 miles with the wind. If the wind speed is a constant 20 miles per hour, how fast would the plane travel in still air?

Plane speed x mph

wind speed 20 mph

against wind x - 20 mph

with wind x + 20 mph

Distance against wind 140

Distance with wind 160

Time = same equate the time against with time with current

t=d/r

140 /(x- 20 )= 160 /(x+ 20 )

140 *(x+ 20 )= 160 *(x- 20 )

140 x + 2800 = 160 x -3200

140 x -160 x = -3200 + -2800

-20 x = -6000

/ -20

x= 300 mph

$4

step-by-step explanation:

$30×5=$150

$150 minus $130=$20

$20÷5=$4.

hope to and hope that my answer is brainliest.(follow me )

option a is correct.

step-by-step explanation:

scale factor: it is used to find proportional measurements.

proportions means having the same ratio.

scale factor is the ratio of the model measurement to the actual measurement in a simplest form.

or we can say that the ratio of any two corresponding lengths in two similar geometric figures

if the scale factor is more than 1, then it is an enlargement,

if the scale factor less than 1, then it is a reduction.

given the two geometric figure:

by definition of proportions, we have