Add 81/21 and 42/5
1st number: 3 18/21, 2nd number: 8 2/5
81/21 + 42/5 is 429/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
81/21 = 81 × 5/21 × 5 = 405/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
42/5 = 42 × 21/5 × 21 = 882/105 - Add the two like fractions:
405/105 + 882/105 = 405 + 882/105 = 1287/105 - 1287/105 simplified gives 429/35
- So, 81/21 + 42/5 = 429/35
In mixed form: 129/35
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