Subtract 28/30 from 15/40
15/40 - 28/30 is -67/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 30 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
15/40 = 15 × 3/40 × 3 = 45/120 - Likewise, for the 2nd fraction, since 30 × 4 = 120,
28/30 = 28 × 4/30 × 4 = 112/120 - Subtract the two like fractions:
45/120 - 112/120 = 45 - 112/120 = -67/120
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