Subtract 21/12 from 90/70
1st number: 1 20/70, 2nd number: 1 9/12
90/70 - 21/12 is -13/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 12 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 70 × 6 = 420,
90/70 = 90 × 6/70 × 6 = 540/420 - Likewise, for the 2nd fraction, since 12 × 35 = 420,
21/12 = 21 × 35/12 × 35 = 735/420 - Subtract the two like fractions:
540/420 - 735/420 = 540 - 735/420 = -195/420 - After reducing the fraction, the answer is -13/28
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