Subtract 42/72 from 30/80
30/80 - 42/72 is -5/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 72 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
30/80 = 30 × 9/80 × 9 = 270/720 - Likewise, for the 2nd fraction, since 72 × 10 = 720,
42/72 = 42 × 10/72 × 10 = 420/720 - Subtract the two like fractions:
270/720 - 420/720 = 270 - 420/720 = -150/720 - After reducing the fraction, the answer is -5/24
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