Add 15/9 and 28/21
1st number: 1 6/9, 2nd number: 1 7/21
15/9 + 28/21 is 3/1.
Steps for adding 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,
15/9 = 15 × 7/9 × 7 = 105/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
28/21 = 28 × 3/21 × 3 = 84/63 - Add the two like fractions:
105/63 + 84/63 = 105 + 84/63 = 189/63 - 189/63 simplified gives 3/1
- So, 15/9 + 28/21 = 3/1
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