Subtract 3/21 from 25/20, Solve 1 5/20

Subtract 3/21 from 25/20

1^st number: 1 5/20, 2^nd number: 3/21

25/20 - 3/21 is 31/28.

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,
25/20 = 25 × 21/20 × 21 = 525/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
3/21 = 3 × 20/21 × 20 = 60/420
Subtract the two like fractions:
525/420 - 60/420 = 525 - 60/420 = 465/420
After reducing the fraction, the answer is 31/28
In mixed form: 13/28

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