Subtract 42/45 from 81/2
1st number: 40 1/2, 2nd number: 42/45
81/2 - 42/45 is 1187/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 2 × 45 = 90,
81/2 = 81 × 45/2 × 45 = 3645/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
42/45 = 42 × 2/45 × 2 = 84/90 - Subtract the two like fractions:
3645/90 - 84/90 = 3645 - 84/90 = 3561/90 - After reducing the fraction, the answer is 1187/30
- In mixed form: 3917/30
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