Question

Three quarters of the cars in a parking garage are black, 4/7 of the remaining cars are blue, and the rest are silver. If there are 9 silver cars, how many cars are in the parking garage? * 1 point

Answer 1

84 cars

Explanation:

Given that 3/4 of the cars in a parking garage are black, let the number of cars in the garage be T, then

number of black cars = 3T/4, other = T - 3T/4 = T/4

If 4/7 of the remaining cars are blue then

the number of blue cars = 4/7 * T/4 = T/7

Remaining cars = T/4 - T/7

= (7T-4T)/28

=3T/28

Given that the remaining cars are sliver and the number of silver cars is 9 then

3T/28 = 9

Cross multiply

3T = 28 * 9

Divide both sides by 3

T = 28 * 9 / 3

= 28 * 3

= 84 Car