Subtract 72/15 from 30/8
1st number: 3 6/8, 2nd number: 4 12/15
30/8 - 72/15 is -21/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 15 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 8 × 15 = 120,
30/8 = 30 × 15/8 × 15 = 450/120 - Likewise, for the 2nd fraction, since 15 × 8 = 120,
72/15 = 72 × 8/15 × 8 = 576/120 - Subtract the two like fractions:
450/120 - 576/120 = 450 - 576/120 = -126/120 - After reducing the fraction, the answer is -21/20
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