Word Problem need help... PLEASE!

To qualify for the indianapolis 500 auto race, each driver must complete two laps of 5-mile track at an average speed of 200mph. Due to some problems at the start, Naomi averages only 160 mph on her first lap. How fast must she go on the second lap to qualify for the face?

Question

Word Problem need help... PLEASE!

To qualify for the indianapolis 500 auto race, each driver must complete two laps of 5-mile track at an average speed of 200mph. Due to some problems at the start, Naomi averages only 160 mph on her first lap. How fast must she go on the second lap to qualify for the face?

anonymous · Answer

The time it takes driving 200mph the whole 10 miles must equal the time it takes driving the first lap at 160mph and the second lap at x mph.
Time = Distance over Speed
10 miles / 200 mph =5 miles / 160 mph + 5 miles / x mph
Solve that for x.

anonymous · Answer

X = 165 mph