Add 5/21 and 15/9
1st number: 5/21, 2nd number: 1 6/9
5/21 + 15/9 is 40/21.
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,
5/21 = 5 × 3/21 × 3 = 15/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
15/9 = 15 × 7/9 × 7 = 105/63 - Add the two like fractions:
15/63 + 105/63 = 15 + 105/63 = 120/63 - 120/63 simplified gives 40/21
- So, 5/21 + 15/9 = 40/21
In mixed form: 119/21
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