Subtract 20/5 from 72/42
1st number: 1 30/42, 2nd number: 4 0/5
72/42 - 20/5 is -16/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 5 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 5 × 42 = 210,
20/5 = 20 × 42/5 × 42 = 840/210 - Subtract the two like fractions:
360/210 - 840/210 = 360 - 840/210 = -480/210 - After reducing the fraction, the answer is -16/7
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