Example

Solving a Word Problem for the Number of Boys in a Study Group

Apply the seven-step problem-solving strategy to a word problem in which one quantity is described using two combined operations — multiplication and addition — applied to the unknown.

Problem: In a study group, the number of girls was three more than twice the number of boys. There were 1111 girls. How many boys were in the study group?

  1. Read the problem carefully and confirm that every word is understood.
  2. Identify what to find: the number of boys in the study group.
  3. Name the unknown: Let nn = the number of boys.
  4. Translate into an equation: The phrase "three more than twice the number of boys" combines two operations — "twice" signals multiplication by 22, and "three more than" signals adding 33 to that product. So the number of girls equals 2n+32n + 3. Since there are 1111 girls:

11=2n+311 = 2n + 3

  1. Solve using a two-step process. First, subtract 33 from both sides to undo the addition:

113=2n+3311 - 3 = 2n + 3 - 3

8=2n8 = 2n

Then divide both sides by 22 to isolate nn:

82=2n2\frac{8}{2} = \frac{2n}{2}

4=n4 = n

  1. Check: Is 44 boys reasonable for a study group? Yes. Does "three more than twice 44" equal 1111? Twice 44 is 88; three more than 88 is 1111. \checkmark
  2. Answer: There were 44 boys in the study group.

This example shows how the phrase "more than twice" combines multiplication and addition into a single algebraic expression, producing a two-step equation that requires both subtraction and division to solve. Unlike problems where the translation involves only one operation, multi-operation phrases demand careful attention to the order in which the operations are applied to the unknown.

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Updated 2026-04-21

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