Add 21/5 and 81/18
1st number: 4 1/5, 2nd number: 4 9/18
21/5 + 81/18 is 87/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 5 × 18 = 90,
21/5 = 21 × 18/5 × 18 = 378/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
81/18 = 81 × 5/18 × 5 = 405/90 - Add the two like fractions:
378/90 + 405/90 = 378 + 405/90 = 783/90 - 783/90 simplified gives 87/10
- So, 21/5 + 81/18 = 87/10
In mixed form: 87/10
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