Add 18/21 and 21/42
18/21 + 21/42 is 19/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
18/21 = 18 × 2/21 × 2 = 36/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
21/42 = 21 × 1/42 × 1 = 21/42 - Add the two like fractions:
36/42 + 21/42 = 36 + 21/42 = 57/42 - 57/42 simplified gives 19/14
- So, 18/21 + 21/42 = 19/14
In mixed form: 15/14
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