Subtract 72/20 from 63/42
1st number: 1 21/42, 2nd number: 3 12/20
63/42 - 72/20 is -21/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
63/42 = 63 × 10/42 × 10 = 630/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420 - Subtract the two like fractions:
630/420 - 1512/420 = 630 - 1512/420 = -882/420 - After reducing the fraction, the answer is -21/10
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