Subtract 81/40 from 90/12, Solve 7 6/12

Subtract 81/40 from 90/12

1^st number: 7 6/12, 2^nd number: 2 1/40

90/12 - 81/40 is 219/40.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 40 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 12 × 10 = 120,
90/12 = 90 × 10/12 × 10 = 900/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
81/40 = 81 × 3/40 × 3 = 243/120
Subtract the two like fractions:
900/120 - 243/120 = 900 - 243/120 = 657/120
After reducing the fraction, the answer is 219/40
In mixed form: 519/40

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