During the last 5 days, John ran 5 miles per day on average. How many miles must he run tomorrow to increase his daily average to 7 miles per day.	Choose the correct choice from the following answers.
A) 2 B) 7 C) 17 D) 30 E) 32
Solution   Average after 6 days = 7   âˆ´ Required miles to run= (6 days x 7 miles/day)-(5 days x 5 miles/day)   = 42 - 25= 
<gadget id="calculator">42 - 25</gadget>
<output>17</output>
17.   Answer 17
<result>C</result>
During the last 5 days, John ran 5 miles per day on average. How many miles must he run tomorrow to increase his daily average to 7 miles per day.