Add 21/42 and 18/10
1st number: 21/42, 2nd number: 1 8/10
21/42 + 18/10 is 23/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 10 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 10 × 21 = 210,
18/10 = 18 × 21/10 × 21 = 378/210 - Add the two like fractions:
105/210 + 378/210 = 105 + 378/210 = 483/210 - 483/210 simplified gives 23/10
- So, 21/42 + 18/10 = 23/10
In mixed form: 23/10
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