Subtract 25/20 from 10/21, Solve 10/21

Subtract 25/20 from 10/21

1^st number: 10/21, 2^nd number: 1 5/20

10/21 - 25/20 is -65/84.

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

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
10/21 = 10 × 20/21 × 20 = 200/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
25/20 = 25 × 21/20 × 21 = 525/420
Subtract the two like fractions:
200/420 - 525/420 = 200 - 525/420 = -325/420
After reducing the fraction, the answer is -65/84

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