Subtract 81/7 from 42/30
1st number: 1 12/30, 2nd number: 11 4/7
42/30 - 81/7 is -356/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 7 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
42/30 = 42 × 7/30 × 7 = 294/210 - Likewise, for the 2nd fraction, since 7 × 30 = 210,
81/7 = 81 × 30/7 × 30 = 2430/210 - Subtract the two like fractions:
294/210 - 2430/210 = 294 - 2430/210 = -2136/210 - After reducing the fraction, the answer is -356/35
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