Subtract 15/21 from 18/9
1st number: 2 0/9, 2nd number: 15/21
18/9 - 15/21 is 9/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 9 × 7 = 63,
18/9 = 18 × 7/9 × 7 = 126/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
15/21 = 15 × 3/21 × 3 = 45/63 - Subtract the two like fractions:
126/63 - 45/63 = 126 - 45/63 = 81/63 - After reducing the fraction, the answer is 9/7
- In mixed form: 12/7
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