Add 8/5 and 15/21
1st number: 1 3/5, 2nd number: 15/21
8/5 + 15/21 is 81/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
8/5 = 8 × 21/5 × 21 = 168/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
15/21 = 15 × 5/21 × 5 = 75/105 - Add the two like fractions:
168/105 + 75/105 = 168 + 75/105 = 243/105 - 243/105 simplified gives 81/35
- So, 8/5 + 15/21 = 81/35
In mixed form: 211/35
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