Subtract 70/21 from 42/15
1st number: 2 12/15, 2nd number: 3 7/21
42/15 - 70/21 is -8/15.
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,
42/15 = 42 × 7/15 × 7 = 294/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
70/21 = 70 × 5/21 × 5 = 350/105 - Subtract the two like fractions:
294/105 - 350/105 = 294 - 350/105 = -56/105 - After reducing the fraction, the answer is -8/15
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