Subtract 40/90 from 12/30
12/30 - 40/90 is -2/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
12/30 = 12 × 3/30 × 3 = 36/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
40/90 = 40 × 1/90 × 1 = 40/90 - Subtract the two like fractions:
36/90 - 40/90 = 36 - 40/90 = -4/90 - After reducing the fraction, the answer is -2/45
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