GED Math Practice Questions: Unit Rates and Scale Factors

In the Mathematical Reasoning section of the GED, you may run across a few problems that deal with unit rates and scale factors. The following practice questions are typical of what you’ll find.

Practice questions

  1. David is very involved with speed walking. To keep from getting too bored, he has started counting how many breaths he takes for each of his steps. He figured that he takes 3 breaths for every 24-inch step. How many breaths does he take in a 1,500-yard walk?

    A. 6,750

    B. 2,250

    C. 1,875

    D. not enough information given

  2. Paul is emptying his swimming pool. He can pump 11 cubic feet of water per minute. If his pool measures 16 yards by 5 yards with an average depth of 4 feet, when will his pool be empty if he starts pumping at noon on Tuesday?

Answers and explanations

  1. A.

    6,750. 1,500 yard walk = 54,000 inches = 2,250 steps = 6,750 breaths.

  2. 4:22 p.m.

    The volume of Paul’s pool is 16 yards = 48 feet by 5 yards = 15 feet by 4 feet = 2,880 cubic feet.

    His pump can handle 11 cubic feet per minute, and it would take


    minutes, or 4.36 hours, or 4 hours and 22 minutes, to empty the pool. If he started pumping at noon on Tuesday, he would finish at 4:22 p.m.