Subtract 30/8 from 42/18
1st number: 2 6/18, 2nd number: 3 6/8
42/18 - 30/8 is -17/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
42/18 = 42 × 4/18 × 4 = 168/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
30/8 = 30 × 9/8 × 9 = 270/72 - Subtract the two like fractions:
168/72 - 270/72 = 168 - 270/72 = -102/72 - After reducing the fraction, the answer is -17/12
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