A 321-inch candle burns down in 7 hours. Assuming the candles are the same thickness and make (that is, directly proportional), how long would it take a 5 -inch candle to burn down?Answer: hours
Q. A 321-inch candle burns down in 7 hours. Assuming the candles are the same thickness and make (that is, directly proportional), how long would it take a 5 -inch candle to burn down?Answer: hours
Set Proportion: We know:● Time taken for a 3.5-inch candle to burn down: 7 hours● Time taken for a 5-inch candle to burn down: x hoursChoose a proportion that represents the problem.3.57=5x
Cross-Multiply: We have: 3.57=5xSelect the equation rewritten after cross-multiplying.The two cross products:7×5 and 3.5×xSo the equation becomes 7×5=3.5×x
Simplify Equation: We have: 7×5=3.5×xSelect the equation we get after simplifying both sides.7×5=3.5×x35=3.5x
Solve for x:35=3.5xSolve for x.35=3.5x3.535=3.53.5x10=xIt would take 10 hours for a 5-inch candle to burn down.
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