Subtract 27/21 from 20/45, Solve 20/45

Subtract 27/21 from 20/45

1^st number: 20/45, 2^nd number: 1 6/21

20/45 - 27/21 is -53/63.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 45 × 7 = 315,
20/45 = 20 × 7/45 × 7 = 140/315
Likewise, for the 2nd fraction, since 21 × 15 = 315,
27/21 = 27 × 15/21 × 15 = 405/315
Subtract the two like fractions:
140/315 - 405/315 = 140 - 405/315 = -265/315
After reducing the fraction, the answer is -53/63

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