Subtract 18/80 from 90/12, Solve 7 6/12

Subtract 18/80 from 90/12

1^st number: 7 6/12, 2^nd number: 18/80

90/12 - 18/80 is 291/40.

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,
18/80 = 18 × 3/80 × 3 = 54/240
Subtract the two like fractions:
1800/240 - 54/240 = 1800 - 54/240 = 1746/240
After reducing the fraction, the answer is 291/40
In mixed form: 711/40

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