Add 18/21 and 20/42
18/21 + 20/42 is 4/3.
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,
20/42 = 20 × 1/42 × 1 = 20/42 - Add the two like fractions:
36/42 + 20/42 = 36 + 20/42 = 56/42 - 56/42 simplified gives 4/3
- So, 18/21 + 20/42 = 4/3
In mixed form: 11/3
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