Bob wants to run a mile in the same time as his sister. If Bob’s time for a mile is currently 10 minutes and his sister’s time is currently 9 minutes 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 options:
A) 3%  B) 5%  C) 8%  D) 10%  E) 12%
Bob's time = 600 secs.   His sis' time = 540 secs.   Percent increase needed = (600-540/600) * 100 = 60/600 * 100= 
<gadget id="calculator">60/600 * 100</gadget>
<output>10</output>
10%. Ans (10%).
<result>D</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 and his sister’s time is currently 9 minutes by what percent does Bob need to improve his time in order run a mile in the same time as his sister?