Problem solved; thanks Thaakisfox!(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

A race car driver must average 200km/hr for six laps of the race track to qualify for a race. If he averages only 150 km/h for the first two laps, calculate the average velocity he must have over the last four laps in order to qualify.

2. Relevant equations

V_{avg}= (X_{2}- X_{1}) / (T_{2}- T_{1})

3. The attempt at a solution

Set V average = 200 km/hr.

200 = [150+ 4(v)]/6

1200 = 150+4v

1350/4 = V for last 4 laps?

337.5 km/h per lap for the last 4 laps?

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Review Q #2

**Physics Forums | Science Articles, Homework Help, Discussion**