Subtract 21/4 from 42/9
1st number: 4 6/9, 2nd number: 5 1/4
42/9 - 21/4 is -7/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 4 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 9 × 4 = 36,
42/9 = 42 × 4/9 × 4 = 168/36 - Likewise, for the 2nd fraction, since 4 × 9 = 36,
21/4 = 21 × 9/4 × 9 = 189/36 - Subtract the two like fractions:
168/36 - 189/36 = 168 - 189/36 = -21/36 - After reducing the fraction, the answer is -7/12
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