Subtract 42/80 from 7/72
7/72 - 42/80 is -77/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 72 × 10 = 720,
7/72 = 7 × 10/72 × 10 = 70/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
42/80 = 42 × 9/80 × 9 = 378/720 - Subtract the two like fractions:
70/720 - 378/720 = 70 - 378/720 = -308/720 - After reducing the fraction, the answer is -77/180
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