Add 81/84 and 21/20
1st number: 81/84, 2nd number: 1 1/20
81/84 + 21/20 is 141/70.
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,
21/20 = 21 × 21/20 × 21 = 441/420 - Add the two like fractions:
405/420 + 441/420 = 405 + 441/420 = 846/420 - 846/420 simplified gives 141/70
- So, 81/84 + 21/20 = 141/70
In mixed form: 21/70
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