Subtract 84/9 from 42/21
1st number: 2 0/21, 2nd number: 9 3/9
42/21 - 84/9 is -22/3.
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,
42/21 = 42 × 3/21 × 3 = 126/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
84/9 = 84 × 7/9 × 7 = 588/63 - Subtract the two like fractions:
126/63 - 588/63 = 126 - 588/63 = -462/63 - After reducing the fraction, the answer is -22/3
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