Subtract 81/80 from 20/15
1st number: 1 5/15, 2nd number: 1 1/80
20/15 - 81/80 is 77/240.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 80 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 15 × 16 = 240,
20/15 = 20 × 16/15 × 16 = 320/240 - Likewise, for the 2nd fraction, since 80 × 3 = 240,
81/80 = 81 × 3/80 × 3 = 243/240 - Subtract the two like fractions:
320/240 - 243/240 = 320 - 243/240 = 77/240
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