Subtract 42/30 from 81/2
1st number: 40 1/2, 2nd number: 1 12/30
81/2 - 42/30 is 391/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 30 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 2 × 15 = 30,
81/2 = 81 × 15/2 × 15 = 1215/30 - Likewise, for the 2nd fraction, since 30 × 1 = 30,
42/30 = 42 × 1/30 × 1 = 42/30 - Subtract the two like fractions:
1215/30 - 42/30 = 1215 - 42/30 = 1173/30 - After reducing the fraction, the answer is 391/10
- In mixed form: 391/10
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