Subtract 30/45 from 20/28, Solve 20/28

Subtract 30/45 from 20/28

20/28 - 30/45 is 1/21.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 45 is 1260

Next, find the equivalent fraction of both fractional numbers with denominator 1260
For the 1st fraction, since 28 × 45 = 1260,
20/28 = 20 × 45/28 × 45 = 900/1260
Likewise, for the 2nd fraction, since 45 × 28 = 1260,
30/45 = 30 × 28/45 × 28 = 840/1260
Subtract the two like fractions:
900/1260 - 840/1260 = 900 - 840/1260 = 60/1260
After reducing the fraction, the answer is 1/21

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