Subtract 30/80 from 7/2, Solve 3 1/2

Subtract 30/80 from 7/2

1^st number: 3 1/2, 2^nd number: 30/80

7/2 - 30/80 is 25/8.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 80 is 80

Next, find the equivalent fraction of both fractional numbers with denominator 80
For the 1st fraction, since 2 × 40 = 80,
7/2 = 7 × 40/2 × 40 = 280/80
Likewise, for the 2nd fraction, since 80 × 1 = 80,
30/80 = 30 × 1/80 × 1 = 30/80
Subtract the two like fractions:
280/80 - 30/80 = 280 - 30/80 = 250/80
After reducing the fraction, the answer is 25/8
In mixed form: 31/8

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