Subtract 90/70 from 15/12
1st number: 1 3/12, 2nd number: 1 20/70
15/12 - 90/70 is -1/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 12 × 35 = 420,
15/12 = 15 × 35/12 × 35 = 525/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
90/70 = 90 × 6/70 × 6 = 540/420 - Subtract the two like fractions:
525/420 - 540/420 = 525 - 540/420 = -15/420 - After reducing the fraction, the answer is -1/28
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