Subtract 42/24 from 21/25, Solve 21/25

Subtract 42/24 from 21/25

1^st number: 21/25, 2^nd number: 1 18/24

21/25 - 42/24 is -91/100.

Find the least common denominator or LCM of the two denominators:
LCM of 25 and 24 is 600

Next, find the equivalent fraction of both fractional numbers with denominator 600
For the 1st fraction, since 25 × 24 = 600,
21/25 = 21 × 24/25 × 24 = 504/600
Likewise, for the 2nd fraction, since 24 × 25 = 600,
42/24 = 42 × 25/24 × 25 = 1050/600
Subtract the two like fractions:
504/600 - 1050/600 = 504 - 1050/600 = -546/600
After reducing the fraction, the answer is -91/100

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