Sarrah

Sarrah bought cupcakes for her family. Thirty-six cupcakes are chocolate, and the rest are red velvet. If 80% of all the cupcakes she bought are chocolate, how many red velvet cupcakes did she buy?

Correct answer:

r =  9

Step-by-step explanation:

$$\begin{gathered} c=36 \\ q=80\%=\frac{80}{100}=\frac{4}{5}=0.8 \\ q\cdot n=c \\ 0.8\cdot n=36 \\ 0.8n=36 \\ n=\frac{36}{0.8}=45 \\ n=45 \\ r=n-c=45-36=9 \end{gathered}$$

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