Subtract 25/20 from 84/21, Solve 4 0/21

Subtract 25/20 from 84/21

1^st number: 4 0/21, 2^nd number: 1 5/20

84/21 - 25/20 is 11/4.

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,
84/21 = 84 × 20/21 × 20 = 1680/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
25/20 = 25 × 21/20 × 21 = 525/420
Subtract the two like fractions:
1680/420 - 525/420 = 1680 - 525/420 = 1155/420
After reducing the fraction, the answer is 11/4
In mixed form: 23/4

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