Use the following information to answer questions 49-51.

For exercise, Jill and Matt run on a 400-meter-long oval track. Jill and Matt each run 10 laps daily and both run in the same lane

50. Today, Jill averaged 70 seconds per lap until she began the last lap. She then slowed down. She averaged 72 seconds per lap for her daily run. How many seconds did Jill take to run the last lap?

Answer and Explanation

Your Answer is

Correct Answer is K

Explanation

J ran 9 laps with an average of 70 seconds per lap, then ran a total of 9×70=630 seconds, ten laps ran 10×72 = 720 seconds, and the tenth lap ran 720-630=90 seconds. Choose K