Subtract 72/63 from 21/7
1st number: 3 0/7, 2nd number: 1 9/63
21/7 - 72/63 is 13/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 63 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 7 × 9 = 63,
21/7 = 21 × 9/7 × 9 = 189/63 - Likewise, for the 2nd fraction, since 63 × 1 = 63,
72/63 = 72 × 1/63 × 1 = 72/63 - Subtract the two like fractions:
189/63 - 72/63 = 189 - 72/63 = 117/63 - After reducing the fraction, the answer is 13/7
- In mixed form: 16/7
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