Question Detail

step-by-step answer to: Alex earned $20. He earned 1/4 of the amount of Rob earned. How much did Rob earn? Write an equation to match the story.

Nov 1, 2016 8:05pm

  • Math
  • 5

2

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    • Nov 7, 2016 9:27am

      Alex = A , Rob = R

      A = 20
      A = 1/4(R)

      Substitute A = 20 into second equation

      20 = 1/4(R)

      Multiply both sides by 4

      80 = R

      Rob earned $80

      • Dec 1, 2016 8:52pm

        I would show with a bar model of alex being one bar and Rob being four bars. If alex has a bar of 20- then Rob's four bars would be 80. So. 4(20) = 80