Subtract 28/9 from 21/7
1st number: 3 0/7, 2nd number: 3 1/9
21/7 - 28/9 is -1/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 9 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 9 × 7 = 63,
28/9 = 28 × 7/9 × 7 = 196/63 - Subtract the two like fractions:
189/63 - 196/63 = 189 - 196/63 = -7/63 - After reducing the fraction, the answer is -1/9
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