Subtract 21/40 from 80/30
1st number: 2 20/30, 2nd number: 21/40
80/30 - 21/40 is 257/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
80/30 = 80 × 4/30 × 4 = 320/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Subtract the two like fractions:
320/120 - 63/120 = 320 - 63/120 = 257/120 - In mixed form: 217/120
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