Subtract 30/84 from 42/81
42/81 - 30/84 is 61/378.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 84 is 2268
Next, find the equivalent fraction of both fractional numbers with denominator 2268 - For the 1st fraction, since 81 × 28 = 2268,
42/81 = 42 × 28/81 × 28 = 1176/2268 - Likewise, for the 2nd fraction, since 84 × 27 = 2268,
30/84 = 30 × 27/84 × 27 = 810/2268 - Subtract the two like fractions:
1176/2268 - 810/2268 = 1176 - 810/2268 = 366/2268 - After reducing the fraction, the answer is 61/378
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