Subtract 81/80 from 90/12
1st number: 7 6/12, 2nd number: 1 1/80
90/12 - 81/80 is 519/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 80 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 12 × 20 = 240,
90/12 = 90 × 20/12 × 20 = 1800/240 - Likewise, for the 2nd fraction, since 80 × 3 = 240,
81/80 = 81 × 3/80 × 3 = 243/240 - Subtract the two like fractions:
1800/240 - 243/240 = 1800 - 243/240 = 1557/240 - After reducing the fraction, the answer is 519/80
- In mixed form: 639/80
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