Add 81/84 and 18/5
1st number: 81/84, 2nd number: 3 3/5
81/84 + 18/5 is 639/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 5 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
81/84 = 81 × 5/84 × 5 = 405/420 - Likewise, for the 2nd fraction, since 5 × 84 = 420,
18/5 = 18 × 84/5 × 84 = 1512/420 - Add the two like fractions:
405/420 + 1512/420 = 405 + 1512/420 = 1917/420 - 1917/420 simplified gives 639/140
- So, 81/84 + 18/5 = 639/140
In mixed form: 479/140
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