Subtract 42/80 from 21/18
1st number: 1 3/18, 2nd number: 42/80
21/18 - 42/80 is 77/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 18 × 40 = 720,
21/18 = 21 × 40/18 × 40 = 840/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
42/80 = 42 × 9/80 × 9 = 378/720 - Subtract the two like fractions:
840/720 - 378/720 = 840 - 378/720 = 462/720 - After reducing the fraction, the answer is 77/120
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