School library

The school library contains 6300 books. These comprise 7% of professional books for teachers, 18% of interest books and encyclopedias for pupils, and the rest of the fairy tales. How much are which books each type?

Final Answer:

a =  441
b =  1134
c =  4725

Step-by-step explanation:

$$\begin{gathered} n=6300 \\ {r}_1=7\%=\frac{7}{100}=0.07 \\ {r}_2=18\%=\frac{18}{100}=\frac{9}{50}=0.18 \\ a=r_1\cdot n=0.07\cdot 6300=441 \end{gathered}$$

$b=n\cdot r_2=6300\cdot 0.18=1134$

$c=n-a-b=6300-441-1134=4725$

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