Subtract 15/9 from 15/21
1st number: 15/21, 2nd number: 1 6/9
15/21 - 15/9 is -20/21.
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,
15/21 = 15 × 3/21 × 3 = 45/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
15/9 = 15 × 7/9 × 7 = 105/63 - Subtract the two like fractions:
45/63 - 105/63 = 45 - 105/63 = -60/63 - After reducing the fraction, the answer is -20/21
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