Add 21/5 and 81/42
1st number: 4 1/5, 2nd number: 1 39/42
21/5 + 81/42 is 429/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 5 × 42 = 210,
21/5 = 21 × 42/5 × 42 = 882/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
81/42 = 81 × 5/42 × 5 = 405/210 - Add the two like fractions:
882/210 + 405/210 = 882 + 405/210 = 1287/210 - 1287/210 simplified gives 429/70
- So, 21/5 + 81/42 = 429/70
In mixed form: 69/70
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