Subtract 8/21 from 40/54
40/54 - 8/21 is 68/189.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
40/54 = 40 × 7/54 × 7 = 280/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
8/21 = 8 × 18/21 × 18 = 144/378 - Subtract the two like fractions:
280/378 - 144/378 = 280 - 144/378 = 136/378 - After reducing the fraction, the answer is 68/189
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