Subtract 81/10 from 72/42
1st number: 1 30/42, 2nd number: 8 1/10
72/42 - 81/10 is -447/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
72/42 = 72 × 5/42 × 5 = 360/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
81/10 = 81 × 21/10 × 21 = 1701/210 - Subtract the two like fractions:
360/210 - 1701/210 = 360 - 1701/210 = -1341/210 - After reducing the fraction, the answer is -447/70
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