Subtract 70/42 from 18/21
1st number: 18/21, 2nd number: 1 28/42
18/21 - 70/42 is -17/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
18/21 = 18 × 2/21 × 2 = 36/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
70/42 = 70 × 1/42 × 1 = 70/42 - Subtract the two like fractions:
36/42 - 70/42 = 36 - 70/42 = -34/42 - After reducing the fraction, the answer is -17/21
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