Subtract 15/7 from 18/20
1st number: 18/20, 2nd number: 2 1/7
18/20 - 15/7 is -87/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 7 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
18/20 = 18 × 7/20 × 7 = 126/140 - Likewise, for the 2nd fraction, since 7 × 20 = 140,
15/7 = 15 × 20/7 × 20 = 300/140 - Subtract the two like fractions:
126/140 - 300/140 = 126 - 300/140 = -174/140 - After reducing the fraction, the answer is -87/70
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