Subtract 21/18 from 42/8
1st number: 5 2/8, 2nd number: 1 3/18
42/8 - 21/18 is 49/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 18 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 8 × 9 = 72,
42/8 = 42 × 9/8 × 9 = 378/72 - Likewise, for the 2nd fraction, since 18 × 4 = 72,
21/18 = 21 × 4/18 × 4 = 84/72 - Subtract the two like fractions:
378/72 - 84/72 = 378 - 84/72 = 294/72 - After reducing the fraction, the answer is 49/12
- In mixed form: 41/12
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