Precisely 82697

The tennis player won precisely 55% of the balls during his serve. In doing so, he served less than thirty times. How many times did he serve?

Correct answer:

n =  20

Step-by-step explanation:

$$\begin{gathered} r=55\%=\frac{55}{100}=\frac{11}{20}=0.55 \\ n<30 \\ n\cdot r=int \\ n\cdot 55=100\cdot k \\ 0<n<30 \\ k=10 \\ n=20 \end{gathered}$$

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