Subtract 72/9 from 72/21
1st number: 3 9/21, 2nd number: 8 0/9
72/21 - 72/9 is -32/7.
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,
72/21 = 72 × 3/21 × 3 = 216/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
72/9 = 72 × 7/9 × 7 = 504/63 - Subtract the two like fractions:
216/63 - 504/63 = 216 - 504/63 = -288/63 - After reducing the fraction, the answer is -32/7
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