Subtract 70/54 from 21/42
1st number: 21/42, 2nd number: 1 16/54
21/42 - 70/54 is -43/54.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 42 × 9 = 378,
21/42 = 21 × 9/42 × 9 = 189/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
70/54 = 70 × 7/54 × 7 = 490/378 - Subtract the two like fractions:
189/378 - 490/378 = 189 - 490/378 = -301/378 - After reducing the fraction, the answer is -43/54
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