Add 81/21 and 18/15
1st number: 3 18/21, 2nd number: 1 3/15
81/21 + 18/15 is 177/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
81/21 = 81 × 5/21 × 5 = 405/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
18/15 = 18 × 7/15 × 7 = 126/105 - Add the two like fractions:
405/105 + 126/105 = 405 + 126/105 = 531/105 - 531/105 simplified gives 177/35
- So, 81/21 + 18/15 = 177/35
In mixed form: 52/35
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