Subtract 81/12 from 42/70
1st number: 42/70, 2nd number: 6 9/12
42/70 - 81/12 is -123/20.
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,
42/70 = 42 × 6/70 × 6 = 252/420 - Likewise, for the 2nd fraction, since 12 × 35 = 420,
81/12 = 81 × 35/12 × 35 = 2835/420 - Subtract the two like fractions:
252/420 - 2835/420 = 252 - 2835/420 = -2583/420 - After reducing the fraction, the answer is -123/20
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