Subtract 21/30 from 21/8, Solve 2 5/8

Subtract 21/30 from 21/8

1^st number: 2 5/8, 2^nd number: 21/30

21/8 - 21/30 is 77/40.

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

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 8 × 15 = 120,
21/8 = 21 × 15/8 × 15 = 315/120
Likewise, for the 2nd fraction, since 30 × 4 = 120,
21/30 = 21 × 4/30 × 4 = 84/120
Subtract the two like fractions:
315/120 - 84/120 = 315 - 84/120 = 231/120
After reducing the fraction, the answer is 77/40
In mixed form: 137/40

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