Subtract 40/49 from 21/80
21/80 - 40/49 is -2171/3920.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 49 is 3920
Next, find the equivalent fraction of both fractional numbers with denominator 3920 - For the 1st fraction, since 80 × 49 = 3920,
21/80 = 21 × 49/80 × 49 = 1029/3920 - Likewise, for the 2nd fraction, since 49 × 80 = 3920,
40/49 = 40 × 80/49 × 80 = 3200/3920 - Subtract the two like fractions:
1029/3920 - 3200/3920 = 1029 - 3200/3920 = -2171/3920
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