Subtract 84/21 from 40/42
1st number: 40/42, 2nd number: 4 0/21
40/42 - 84/21 is -64/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
40/42 = 40 × 1/42 × 1 = 40/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
84/21 = 84 × 2/21 × 2 = 168/42 - Subtract the two like fractions:
40/42 - 168/42 = 40 - 168/42 = -128/42 - After reducing the fraction, the answer is -64/21
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