Add 21/42 and 81/5
1st number: 21/42, 2nd number: 16 1/5
21/42 + 81/5 is 167/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 5 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Likewise, for the 2nd fraction, since 5 × 42 = 210,
81/5 = 81 × 42/5 × 42 = 3402/210 - Add the two like fractions:
105/210 + 3402/210 = 105 + 3402/210 = 3507/210 - 3507/210 simplified gives 167/10
- So, 21/42 + 81/5 = 167/10
In mixed form: 167/10
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