Subtract 21/20 from 21/24, Solve 21/24

Subtract 21/20 from 21/24

1^st number: 21/24, 2^nd number: 1 1/20

21/24 - 21/20 is -7/40.

Find the least common denominator or LCM of the two denominators:
LCM of 24 and 20 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 24 × 5 = 120,
21/24 = 21 × 5/24 × 5 = 105/120
Likewise, for the 2nd fraction, since 20 × 6 = 120,
21/20 = 21 × 6/20 × 6 = 126/120
Subtract the two like fractions:
105/120 - 126/120 = 105 - 126/120 = -21/120
After reducing the fraction, the answer is -7/40

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