Subtract 42/90 from 9/40
9/40 - 42/90 is -29/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
9/40 = 9 × 9/40 × 9 = 81/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
42/90 = 42 × 4/90 × 4 = 168/360 - Subtract the two like fractions:
81/360 - 168/360 = 81 - 168/360 = -87/360 - After reducing the fraction, the answer is -29/120
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