Subtract 9/90 from 81/84
81/84 - 9/90 is 121/140.
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,
81/84 = 81 × 15/84 × 15 = 1215/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
9/90 = 9 × 14/90 × 14 = 126/1260 - Subtract the two like fractions:
1215/1260 - 126/1260 = 1215 - 126/1260 = 1089/1260 - After reducing the fraction, the answer is 121/140
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