Subtract 18/63 from 72/21
1st number: 3 9/21, 2nd number: 18/63
72/21 - 18/63 is 22/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
72/21 = 72 × 3/21 × 3 = 216/63 - Likewise, for the 2nd fraction, since 63 × 1 = 63,
18/63 = 18 × 1/63 × 1 = 18/63 - Subtract the two like fractions:
216/63 - 18/63 = 216 - 18/63 = 198/63 - After reducing the fraction, the answer is 22/7
- In mixed form: 31/7
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