Subtract 10/21 from 30/12
1st number: 2 6/12, 2nd number: 10/21
30/12 - 10/21 is 85/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
30/12 = 30 × 7/12 × 7 = 210/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
10/21 = 10 × 4/21 × 4 = 40/84 - Subtract the two like fractions:
210/84 - 40/84 = 210 - 40/84 = 170/84 - After reducing the fraction, the answer is 85/42
- In mixed form: 21/42
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