Subtract 70/80 from 21/50
21/50 - 70/80 is -91/200.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 50 and 80 is 400
Next, find the equivalent fraction of both fractional numbers with denominator 400 - For the 1st fraction, since 50 × 8 = 400,
21/50 = 21 × 8/50 × 8 = 168/400 - Likewise, for the 2nd fraction, since 80 × 5 = 400,
70/80 = 70 × 5/80 × 5 = 350/400 - Subtract the two like fractions:
168/400 - 350/400 = 168 - 350/400 = -182/400 - After reducing the fraction, the answer is -91/200
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