Subtract 12/20 from 9/28
9/28 - 12/20 is -39/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
9/28 = 9 × 5/28 × 5 = 45/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
12/20 = 12 × 7/20 × 7 = 84/140 - Subtract the two like fractions:
45/140 - 84/140 = 45 - 84/140 = -39/140
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