Add 18/42 and 42/21
1st number: 18/42, 2nd number: 2 0/21
18/42 + 42/21 is 17/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
18/42 = 18 × 1/42 × 1 = 18/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
42/21 = 42 × 2/21 × 2 = 84/42 - Add the two like fractions:
18/42 + 84/42 = 18 + 84/42 = 102/42 - 102/42 simplified gives 17/7
- So, 18/42 + 42/21 = 17/7
In mixed form: 23/7
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