Praxis Core Academic Skills for Educators: Mathematics (5733)Number and QuantityMedium

A production manager is analyzing machine output. Machine A produces 120 units in 3 hours. Machine B produces 180 units in 4.5 hours. Machine C produces 150 units in 3.5 hours. Which machine has the highest production rate?

  1. AMachine C
  2. BMachines A and B have the same rate
  3. CMachine B
  4. DMachine A
Show answer & explanation

Correct answer: A. Machine C

To find the highest production rate, calculate the unit rate (units per hour) for each machine by dividing the total units by the total time.

Why the other options are wrong

  • B. Machines A and B both produce 40 units/hour, but Machine C has a higher rate.
  • C. Machine B: 180 units / 4.5 hours = 40 units/hour. This is equal to Machine A.
  • D. Machine A: 120 units / 3 hours = 40 units/hour. This is the highest rate.

Unit Rate

A unit rate describes how many units of the first quantity correspond to one unit of the second quantity. It is often expressed as 'quantity per one unit of another quantity'.

  • Calculated by dividing the first quantity by the second quantity.
  • Useful for comparing different rates or values.
  • Examples: miles per hour, cost per item, units per hour.

Memory trick: Divide to Find the One!

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