Question

Which of the following is not true?

A. $\frac{1}{5}+\frac{2}{7}=\frac{3}{21}+\frac{1}{5}$

B. $\frac{1}{5}\times \frac{2}{7}=\frac{2}{7}\times \frac{1}{5}$

C. $\frac{1}{5}-\frac{2}{7}=\frac{2}{7}-\frac{1}{5}$

D. $\frac{1}{5}+\left(\frac{-2}{7}\right)=\left(\frac{-2}{7}\right)+\frac{1}{5}$

Answer 1

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