Subtract 21/40 from 30/12
1st number: 2 6/12, 2nd number: 21/40
30/12 - 21/40 is 79/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 12 × 10 = 120,
30/12 = 30 × 10/12 × 10 = 300/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Subtract the two like fractions:
300/120 - 63/120 = 300 - 63/120 = 237/120 - After reducing the fraction, the answer is 79/40
- In mixed form: 139/40
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