Subtract 5/49 from 18/21, Solve 18/21

Subtract 5/49 from 18/21

18/21 - 5/49 is 37/49.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 49 is 147

Next, find the equivalent fraction of both fractional numbers with denominator 147
For the 1st fraction, since 21 × 7 = 147,
18/21 = 18 × 7/21 × 7 = 126/147
Likewise, for the 2nd fraction, since 49 × 3 = 147,
5/49 = 5 × 3/49 × 3 = 15/147
Subtract the two like fractions:
126/147 - 15/147 = 126 - 15/147 = 111/147
After reducing the fraction, the answer is 37/49

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