Add 21/2 and 72/81
1st number: 10 1/2, 2nd number: 72/81
21/2 + 72/81 is 205/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 81 is 162
Next, find the equivalent fraction of both fractional numbers with denominator 162 - For the 1st fraction, since 2 × 81 = 162,
21/2 = 21 × 81/2 × 81 = 1701/162 - Likewise, for the 2nd fraction, since 81 × 2 = 162,
72/81 = 72 × 2/81 × 2 = 144/162 - Add the two like fractions:
1701/162 + 144/162 = 1701 + 144/162 = 1845/162 - 1845/162 simplified gives 205/18
- So, 21/2 + 72/81 = 205/18
In mixed form: 117/18
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