Subtract 42/24 from 21/20
1st number: 1 1/20, 2nd number: 1 18/24
21/20 - 42/24 is -7/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 24 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 20 × 6 = 120,
21/20 = 21 × 6/20 × 6 = 126/120 - Likewise, for the 2nd fraction, since 24 × 5 = 120,
42/24 = 42 × 5/24 × 5 = 210/120 - Subtract the two like fractions:
126/120 - 210/120 = 126 - 210/120 = -84/120 - After reducing the fraction, the answer is -7/10
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