Add 21/42 and 3/18
21/42 + 3/18 is 2/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
3/18 = 3 × 7/18 × 7 = 21/126 - Add the two like fractions:
63/126 + 21/126 = 63 + 21/126 = 84/126 - 84/126 simplified gives 2/3
- So, 21/42 + 3/18 = 2/3
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