Add 21/10 and 81/42
1st number: 2 1/10, 2nd number: 1 39/42
21/10 + 81/42 is 141/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
21/10 = 21 × 21/10 × 21 = 441/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
81/42 = 81 × 5/42 × 5 = 405/210 - Add the two like fractions:
441/210 + 405/210 = 441 + 405/210 = 846/210 - 846/210 simplified gives 141/35
- So, 21/10 + 81/42 = 141/35
In mixed form: 41/35
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