Subtract 9/10 from 42/90
42/90 - 9/10 is -13/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 10 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
42/90 = 42 × 1/90 × 1 = 42/90 - Likewise, for the 2nd fraction, since 10 × 9 = 90,
9/10 = 9 × 9/10 × 9 = 81/90 - Subtract the two like fractions:
42/90 - 81/90 = 42 - 81/90 = -39/90 - After reducing the fraction, the answer is -13/30
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