Subtract 81/30 from 70/18
1st number: 3 16/18, 2nd number: 2 21/30
70/18 - 81/30 is 107/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 30 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
70/18 = 70 × 5/18 × 5 = 350/90 - Likewise, for the 2nd fraction, since 30 × 3 = 90,
81/30 = 81 × 3/30 × 3 = 243/90 - Subtract the two like fractions:
350/90 - 243/90 = 350 - 243/90 = 107/90 - In mixed form: 117/90
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