Add 1/5 and 81/21
1st number: 1/5, 2nd number: 3 18/21
1/5 + 81/21 is 142/35.
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,
1/5 = 1 × 21/5 × 21 = 21/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
81/21 = 81 × 5/21 × 5 = 405/105 - Add the two like fractions:
21/105 + 405/105 = 21 + 405/105 = 426/105 - 426/105 simplified gives 142/35
- So, 1/5 + 81/21 = 142/35
In mixed form: 42/35
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