Subtract 42/21 from 12/9
1st number: 1 3/9, 2nd number: 2 0/21
12/9 - 42/21 is -2/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 9 × 7 = 63,
12/9 = 12 × 7/9 × 7 = 84/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
42/21 = 42 × 3/21 × 3 = 126/63 - Subtract the two like fractions:
84/63 - 126/63 = 84 - 126/63 = -42/63 - After reducing the fraction, the answer is -2/3
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