Add 18/10 and 42/21
1st number: 1 8/10, 2nd number: 2 0/21
18/10 + 42/21 is 19/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
18/10 = 18 × 21/10 × 21 = 378/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
42/21 = 42 × 10/21 × 10 = 420/210 - Add the two like fractions:
378/210 + 420/210 = 378 + 420/210 = 798/210 - 798/210 simplified gives 19/5
- So, 18/10 + 42/21 = 19/5
In mixed form: 34/5
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