Subtract 40/49 from 21/28
21/28 - 40/49 is -13/196.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 49 is 196
Next, find the equivalent fraction of both fractional numbers with denominator 196 - For the 1st fraction, since 28 × 7 = 196,
21/28 = 21 × 7/28 × 7 = 147/196 - Likewise, for the 2nd fraction, since 49 × 4 = 196,
40/49 = 40 × 4/49 × 4 = 160/196 - Subtract the two like fractions:
147/196 - 160/196 = 147 - 160/196 = -13/196
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