Bob wants to run a mile in the same time as his sister. If Bob’s time for a mile is currently 10 minutes 30 seconds and his sister’s time is currently 9 minutes 36 seconds, by what percent does Bob need to improve his time in order run a mile in the same time as his sister?	Choose the correct choice from the following answers:
A) 3%
B) 5%
C) 9%
D) 10%
E) 12%
Bob's time = 630 secs.   His sis' time = 576 secs.   Percent increase needed = (630-576/630) * 100 = 54/640 * 100 = 9%. Ans (9%).
<result>C</result>
Bob wants to run a mile in the same time as his sister. If Bob’s time for a mile is currently 10 minutes 30 seconds and his sister’s time is currently 9 minutes 36 seconds, by what percent does Bob need to improve his time in order run a mile in the same time as his sister?