Subtract 45/90 from 40/84
40/84 - 45/90 is -1/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 84 × 15 = 1260,
40/84 = 40 × 15/84 × 15 = 600/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
45/90 = 45 × 14/90 × 14 = 630/1260 - Subtract the two like fractions:
600/1260 - 630/1260 = 600 - 630/1260 = -30/1260 - After reducing the fraction, the answer is -1/42
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