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Course: Algebra (all content) > Unit 3

Lesson 14: Linear models word problems
Math
Algebra (all content)
Linear equations, functions, & graphs
Linear models word problems
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Comparing linear rates word problems

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Problem

Two candles start burning at the same time. One candle is 15cm tall and burns at a rate of 5cm every 6 hours. The other candle is 25cm tall and burns at a rate of 212cm every hour.
How tall will the candles be when they first burn down to the same height?
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi
cm