Subtract 81/30 from 80/40
1st number: 2 0/40, 2nd number: 2 21/30
80/40 - 81/30 is -7/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 30 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
80/40 = 80 × 3/40 × 3 = 240/120 - Likewise, for the 2nd fraction, since 30 × 4 = 120,
81/30 = 81 × 4/30 × 4 = 324/120 - Subtract the two like fractions:
240/120 - 324/120 = 240 - 324/120 = -84/120 - After reducing the fraction, the answer is -7/10
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