Twenty air-conditioning units have been brought in for service. Twelve of them have broken compressors, and eight have broken fans. Seven units are chosen at random to be worked on. What is the probability that three of them have broken fans

0.3576

Step-by-step explanation:

Let the probability that the units that have broken fans from the seven units chosen at random be x.

The probability that three of them have broken fans will be 0.3576. Check the attachment for details

let y equal to

the total fare and x is the mile of taxi ride. so the equation is

y = 0.55x + 1.75

since susie has

$10 to spend for a taxi cab, so he can have

10 = 0.55x +

1.75

x = 15 miles of

taxi ride

so the system of

inequality is

10 < 0.55x +

1.75

x > 2

add the numbers under frequency to find the total number:

5 + 8 +7 + 4 + 0 +1 = 25

the answer is 25.