Subtract 30/45 from 81/90
81/90 - 30/45 is 7/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
81/90 = 81 × 1/90 × 1 = 81/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
30/45 = 30 × 2/45 × 2 = 60/90 - Subtract the two like fractions:
81/90 - 60/90 = 81 - 60/90 = 21/90 - After reducing the fraction, the answer is 7/30
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