Subtract 72/42 from 40/30
1st number: 1 10/30, 2nd number: 1 30/42
40/30 - 72/42 is -8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
40/30 = 40 × 7/30 × 7 = 280/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
72/42 = 72 × 5/42 × 5 = 360/210 - Subtract the two like fractions:
280/210 - 360/210 = 280 - 360/210 = -80/210 - After reducing the fraction, the answer is -8/21
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