Subtract 1/7 from 15/20
15/20 - 1/7 is 17/28.
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,
15/20 = 15 × 7/20 × 7 = 105/140 - Likewise, for the 2nd fraction, since 7 × 20 = 140,
1/7 = 1 × 20/7 × 20 = 20/140 - Subtract the two like fractions:
105/140 - 20/140 = 105 - 20/140 = 85/140 - After reducing the fraction, the answer is 17/28
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