Subtract 25/8 from 20/30, Solve 20/30

Subtract 25/8 from 20/30

1^st number: 20/30, 2^nd number: 3 1/8

20/30 - 25/8 is -59/24.

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,
20/30 = 20 × 4/30 × 4 = 80/120
Likewise, for the 2nd fraction, since 8 × 15 = 120,
25/8 = 25 × 15/8 × 15 = 375/120
Subtract the two like fractions:
80/120 - 375/120 = 80 - 375/120 = -295/120
After reducing the fraction, the answer is -59/24

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