Subtract 42/21 from 20/15
1st number: 1 5/15, 2nd number: 2 0/21
20/15 - 42/21 is -2/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
20/15 = 20 × 7/15 × 7 = 140/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
42/21 = 42 × 5/21 × 5 = 210/105 - Subtract the two like fractions:
140/105 - 210/105 = 140 - 210/105 = -70/105 - After reducing the fraction, the answer is -2/3
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