Subtract 81/8 from 25/30, Solve 25/30

Subtract 81/8 from 25/30

1^st number: 25/30, 2^nd number: 10 1/8

25/30 - 81/8 is -223/24.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 8 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 30 × 4 = 120,
25/30 = 25 × 4/30 × 4 = 100/120
Likewise, for the 2nd fraction, since 8 × 15 = 120,
81/8 = 81 × 15/8 × 15 = 1215/120
Subtract the two like fractions:
100/120 - 1215/120 = 100 - 1215/120 = -1115/120
After reducing the fraction, the answer is -223/24

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