Subtract 7/8 from 42/90
42/90 - 7/8 is -49/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 8 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
42/90 = 42 × 4/90 × 4 = 168/360 - Likewise, for the 2nd fraction, since 8 × 45 = 360,
7/8 = 7 × 45/8 × 45 = 315/360 - Subtract the two like fractions:
168/360 - 315/360 = 168 - 315/360 = -147/360 - After reducing the fraction, the answer is -49/120
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