Subtract 36/21 from 45/20, Solve 2 5/20

Subtract 36/21 from 45/20

1^st number: 2 5/20, 2^nd number: 1 15/21

45/20 - 36/21 is 15/28.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
45/20 = 45 × 21/20 × 21 = 945/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
36/21 = 36 × 20/21 × 20 = 720/420
Subtract the two like fractions:
945/420 - 720/420 = 945 - 720/420 = 225/420
After reducing the fraction, the answer is 15/28

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