Subtract 72/20 from 9/7
1st number: 1 2/7, 2nd number: 3 12/20
9/7 - 72/20 is -81/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 7 × 20 = 140,
9/7 = 9 × 20/7 × 20 = 180/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
72/20 = 72 × 7/20 × 7 = 504/140 - Subtract the two like fractions:
180/140 - 504/140 = 180 - 504/140 = -324/140 - After reducing the fraction, the answer is -81/35
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