Subtract 72/21 from 24/12
1st number: 2 0/12, 2nd number: 3 9/21
24/12 - 72/21 is -10/7.
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,
24/12 = 24 × 7/12 × 7 = 168/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
72/21 = 72 × 4/21 × 4 = 288/84 - Subtract the two like fractions:
168/84 - 288/84 = 168 - 288/84 = -120/84 - After reducing the fraction, the answer is -10/7
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