A bakery

A bakery makes cylindrical mini muffins that measure 2 inches in diameter and one and one-fourth inches in height. If each mini muffin is completely wrapped in paper, then at least how much paper is needed to wrap 6 mini muffins? Approximate using pi equals 22 over 7.

Correct answer:

S =  47.1429 in²

Step-by-step explanation:

$$\begin{gathered} d=2\text{in} \\ h=\frac{1}{4}=0.25\text{in} \\ n=6 \\ r=d/2=2/2=1\text{in} \\ \pi =\frac{22}{7}\doteq 3.1416 \\ {S}_1=2\pi \cdot r^2+2\pi \cdot r\cdot h=2\cdot \frac{22}{7}\cdot 1^2+2\cdot \frac{22}{7}\cdot 1\cdot \frac{1}{4}=\frac{55}{7}\doteq 7.8571{\text{in}}^2 \\ S=n\cdot S_1=6\cdot \frac{55}{7}=\frac{6\cdot 55}{7}=\frac{330}{7}=\frac{330}{7}{\text{in}}^2=47.1429{\text{in}}^2 \end{gathered}$$

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