Subtract 42/80 from 21/75
21/75 - 42/80 is -49/200.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 80 is 1200
Next, find the equivalent fraction of both fractional numbers with denominator 1200 - For the 1st fraction, since 75 × 16 = 1200,
21/75 = 21 × 16/75 × 16 = 336/1200 - Likewise, for the 2nd fraction, since 80 × 15 = 1200,
42/80 = 42 × 15/80 × 15 = 630/1200 - Subtract the two like fractions:
336/1200 - 630/1200 = 336 - 630/1200 = -294/1200 - After reducing the fraction, the answer is -49/200
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