Subtract 21/8 from 42/36
1st number: 1 6/36, 2nd number: 2 5/8
42/36 - 21/8 is -35/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 36 × 2 = 72,
42/36 = 42 × 2/36 × 2 = 84/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
21/8 = 21 × 9/8 × 9 = 189/72 - Subtract the two like fractions:
84/72 - 189/72 = 84 - 189/72 = -105/72 - After reducing the fraction, the answer is -35/24
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