Add 5/21 and 18/42
5/21 + 18/42 is 2/3.
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,
5/21 = 5 × 2/21 × 2 = 10/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
18/42 = 18 × 1/42 × 1 = 18/42 - Add the two like fractions:
10/42 + 18/42 = 10 + 18/42 = 28/42 - 28/42 simplified gives 2/3
- So, 5/21 + 18/42 = 2/3
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