Add 81/84 and 3/20
81/84 + 3/20 is 39/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 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 20 × 21 = 420,
3/20 = 3 × 21/20 × 21 = 63/420 - Add the two like fractions:
405/420 + 63/420 = 405 + 63/420 = 468/420 - 468/420 simplified gives 39/35
- So, 81/84 + 3/20 = 39/35
In mixed form: 14/35
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