Subtract 42/80 from 7/90
7/90 - 42/80 is -161/360.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
7/90 = 7 × 8/90 × 8 = 56/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
42/80 = 42 × 9/80 × 9 = 378/720 - Subtract the two like fractions:
56/720 - 378/720 = 56 - 378/720 = -322/720 - After reducing the fraction, the answer is -161/360
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