Subtract 9/20 from 3/7
3/7 - 9/20 is -3/140.
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,
3/7 = 3 × 20/7 × 20 = 60/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
9/20 = 9 × 7/20 × 7 = 63/140 - Subtract the two like fractions:
60/140 - 63/140 = 60 - 63/140 = -3/140
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