Add 15/21 and 18/9
1st number: 15/21, 2nd number: 2 0/9
15/21 + 18/9 is 19/7.
Steps for adding 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,
18/9 = 18 × 7/9 × 7 = 126/63 - Add the two like fractions:
45/63 + 126/63 = 45 + 126/63 = 171/63 - 171/63 simplified gives 19/7
- So, 15/21 + 18/9 = 19/7
In mixed form: 25/7
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