a) F, ponieważ:

$\frac{6}{5}=\frac{24}{20}=1\frac{4}{20}$  

$\frac{18}{15}=\frac{6}{5}=1\frac{4}{20}$  

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b) F, ponieważ:

$\frac{1}{2}+\frac{1}{3}=\frac{3}{6}+\frac{2}{6}=\frac{5}{6}$  

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c) P, ponieważ:

$\frac{2}{3}=\frac{16}{24}$  

$\frac{7}{8}=\frac{21}{24}$  

$\frac{3}{4}=\frac{18}{24}$  

Mamy:

$\frac{16}{24}<\frac{18}{24}<\frac{21}{24}$  

czyli

$\frac{2}{3}<\frac{3}{4}<\frac{7}{8}$  

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d) P, ponieważ:

$1-\left(\frac{3}{8}+\frac{1}{4}\right)=\frac{8}{8}-\left(\frac{3}{8}+\frac{2}{8}\right)=\frac{8}{8}-\frac{5}{8}=\frac{3}{8}$