Subtract 18/21 from 21/3
1st number: 7 0/3, 2nd number: 18/21
21/3 - 18/21 is 43/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 21 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 3 × 7 = 21,
21/3 = 21 × 7/3 × 7 = 147/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
18/21 = 18 × 1/21 × 1 = 18/21 - Subtract the two like fractions:
147/21 - 18/21 = 147 - 18/21 = 129/21 - After reducing the fraction, the answer is 43/7
- In mixed form: 61/7
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