Add 15/20 and 81/84
15/20 + 81/84 is 12/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
15/20 = 15 × 21/20 × 21 = 315/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
81/84 = 81 × 5/84 × 5 = 405/420 - Add the two like fractions:
315/420 + 405/420 = 315 + 405/420 = 720/420 - 720/420 simplified gives 12/7
- So, 15/20 + 81/84 = 12/7
In mixed form: 15/7
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