Math Problem Set 3

  1. Sarah jogs 2 miles at 11 minutes per mile and then walks for 3 miles at 17 minutes per mile. What is her average rate in miles per minute.
  2. Jon cycles every Sunday. This past Sunday, he rode 20 miles at 12 miles per hour and another 40 miles at 25 miles per hour. What is his average rate?
  3. Golan also cycles every Sunday. This past Sunday he rode for 30 miles at 25 miles per hour. He then rode an additional 20 miles at an unknown speed. If his average rate was 22 miles per hour, what was the unknown speed?
  4. What is the area of a trapezoid?
  5. What is the midpoint formula?
  6. Andrew drove 100 miles at 50 mph and another 100 miles at 70 mph. What is his average rate?
  7. 2j varies inversely with 7c. When j is 20, c is 18. Find c when j is 12.
  8. The square root of Y varies directly with 2r. What is the value of Y when r is 8. When Y is 225, r is 12.
  9. Z varies jointly with M and 2N. Express Z in terms of M and N