Add 20/5 and 81/21
1st number: 4 0/5, 2nd number: 3 18/21
20/5 + 81/21 is 55/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
20/5 = 20 × 21/5 × 21 = 420/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
81/21 = 81 × 5/21 × 5 = 405/105 - Add the two like fractions:
420/105 + 405/105 = 420 + 405/105 = 825/105 - 825/105 simplified gives 55/7
- So, 20/5 + 81/21 = 55/7
In mixed form: 76/7
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