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Fractions and mixed numbers

# Reciprocals

One number is the reciprocal of another if their product is 1.

The reciprocal of $\frac{5}{6}$ is $\frac{6}{5}$ since $\frac{5}{6}\;\cdot\;\frac{6}{5}=1$

The reciprocal of a fraction is obtained by interchanging the numerator and the denominator, i.e. by inverting the fraction.

Find the reciprocal of $\frac{3}{7}$

Solution:
The reciprocal of $\frac{3}{7}$ is $\frac{7}{3}$

Find the reciprocal of 20

Solution:
The reciprocal of 20 is $\frac{1}{20}$

Find the reciprocal of $\frac{2}{9}$
 Solution: