Subtract 72/15 from 30/42
1st number: 30/42, 2nd number: 4 12/15
30/42 - 72/15 is -143/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 15 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
30/42 = 30 × 5/42 × 5 = 150/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
72/15 = 72 × 14/15 × 14 = 1008/210 - Subtract the two like fractions:
150/210 - 1008/210 = 150 - 1008/210 = -858/210 - After reducing the fraction, the answer is -143/35
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