Cathy lives in a state where speeders are fined $15 for each mile per hour over the speed limit. Cathy was given a ticket for $105 for speeding on a road where the speed limit is 60 miles per hour. How fast was Cathy driving?

Cathy was driving at a speed of 67 miles per hour.

Step-by-step explanation:

Fined $15 for each mile per hour over the speed limit. Cathy was given a ticket for $105.

We solve this using a rule of three.

1 mile - $15

x miles - $105

Applying cross multiplication:

15x = 105

x = 105/5 = 7.

Cathy was 7 miles above the speed limit.

How fast was Cathy driving?

7 miles above the speed limit of 60 miles per hour, so 60 + 7 = 67 miles per hour.

Cathy was driving at a speed of 67 miles per hour.

14.3

step-by-step explanation:

add all the numbers together.

9 + 12 + 15 + 16 + 17 + 17 = 86

now, divide 86 by how many numbers we have: 6.

86 / 6 = 14.3