Subtract 84/42 from 15/20
1st number: 15/20, 2nd number: 2 0/42
15/20 - 84/42 is -5/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
15/20 = 15 × 21/20 × 21 = 315/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
84/42 = 84 × 10/42 × 10 = 840/420 - Subtract the two like fractions:
315/420 - 840/420 = 315 - 840/420 = -525/420 - After reducing the fraction, the answer is -5/4
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