Subtract 21/49 from 42/80
42/80 - 21/49 is 27/280.
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,
42/80 = 42 × 49/80 × 49 = 2058/3920 - Likewise, for the 2nd fraction, since 49 × 80 = 3920,
21/49 = 21 × 80/49 × 80 = 1680/3920 - Subtract the two like fractions:
2058/3920 - 1680/3920 = 2058 - 1680/3920 = 378/3920 - After reducing the fraction, the answer is 27/280
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