Wax candles

A company makes wax candles in the shape of a cylinder. Each candle has a diameter of 4 inches and a height of 7 inches. If the company used 7561.12 in³ of wax, how many candles did it make? Use 3.14, and do not round your answer.

Correct answer:

n =  86

Step-by-step explanation:

$$\begin{gathered} D=4\text{inch} \\ h=7\text{inch} \\ V=7561.12{\text{inch}}^3 \\ r=D/2=4/2=2\text{inch} \\ \pi =3.14 \\ {V}_1=3.14\cdot r^2\cdot h=3.14\cdot 2^2\cdot 7=\frac{2198}{25}=87\frac{23}{25}=87.92{\text{inch}}^3 \\ n=V/V_1=7561.12/87.92=86 \end{gathered}$$

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