Subtract 21/20 from 42/48
1st number: 42/48, 2nd number: 1 1/20
42/48 - 21/20 is -7/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 48 and 20 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 48 × 5 = 240,
42/48 = 42 × 5/48 × 5 = 210/240 - Likewise, for the 2nd fraction, since 20 × 12 = 240,
21/20 = 21 × 12/20 × 12 = 252/240 - Subtract the two like fractions:
210/240 - 252/240 = 210 - 252/240 = -42/240 - After reducing the fraction, the answer is -7/40
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