Subtract 5/70 from 21/72, Solve 21/72

Subtract 5/70 from 21/72

21/72 - 5/70 is 37/168.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 70 is 2520

Next, find the equivalent fraction of both fractional numbers with denominator 2520
For the 1st fraction, since 72 × 35 = 2520,
21/72 = 21 × 35/72 × 35 = 735/2520
Likewise, for the 2nd fraction, since 70 × 36 = 2520,
5/70 = 5 × 36/70 × 36 = 180/2520
Subtract the two like fractions:
735/2520 - 180/2520 = 735 - 180/2520 = 555/2520
After reducing the fraction, the answer is 37/168

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