Subtract 42/90 from 3/9
3/9 - 42/90 is -2/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 9 × 10 = 90,
3/9 = 3 × 10/9 × 10 = 30/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
42/90 = 42 × 1/90 × 1 = 42/90 - Subtract the two like fractions:
30/90 - 42/90 = 30 - 42/90 = -12/90 - After reducing the fraction, the answer is -2/15
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