Subtract 49/15 from 20/21
1st number: 20/21, 2nd number: 3 4/15
20/21 - 49/15 is -81/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
20/21 = 20 × 5/21 × 5 = 100/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
49/15 = 49 × 7/15 × 7 = 343/105 - Subtract the two like fractions:
100/105 - 343/105 = 100 - 343/105 = -243/105 - After reducing the fraction, the answer is -81/35
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