Subtract 81/12 from 21/70
1st number: 21/70, 2nd number: 6 9/12
21/70 - 81/12 is -129/20.
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,
21/70 = 21 × 6/70 × 6 = 126/420 - Likewise, for the 2nd fraction, since 12 × 35 = 420,
81/12 = 81 × 35/12 × 35 = 2835/420 - Subtract the two like fractions:
126/420 - 2835/420 = 126 - 2835/420 = -2709/420 - After reducing the fraction, the answer is -129/20
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