Add 21/15 and 81/10
1st number: 1 6/15, 2nd number: 8 1/10
21/15 + 81/10 is 19/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 10 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 15 × 2 = 30,
21/15 = 21 × 2/15 × 2 = 42/30 - Likewise, for the 2nd fraction, since 10 × 3 = 30,
81/10 = 81 × 3/10 × 3 = 243/30 - Add the two like fractions:
42/30 + 243/30 = 42 + 243/30 = 285/30 - 285/30 simplified gives 19/2
- So, 21/15 + 81/10 = 19/2
In mixed form: 91/2
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