Subtract 21/4 from 36/42
1st number: 36/42, 2nd number: 5 1/4
36/42 - 21/4 is -123/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 4 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
36/42 = 36 × 2/42 × 2 = 72/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
21/4 = 21 × 21/4 × 21 = 441/84 - Subtract the two like fractions:
72/84 - 441/84 = 72 - 441/84 = -369/84 - After reducing the fraction, the answer is -123/28
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