Subtract 12/9 from 40/21
1st number: 1 19/21, 2nd number: 1 3/9
40/21 - 12/9 is 4/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
40/21 = 40 × 3/21 × 3 = 120/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
12/9 = 12 × 7/9 × 7 = 84/63 - Subtract the two like fractions:
120/63 - 84/63 = 120 - 84/63 = 36/63 - After reducing the fraction, the answer is 4/7
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