Add 3/21 and 18/42
3/21 + 18/42 is 4/7.
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,
3/21 = 3 × 2/21 × 2 = 6/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
18/42 = 18 × 1/42 × 1 = 18/42 - Add the two like fractions:
6/42 + 18/42 = 6 + 18/42 = 24/42 - 24/42 simplified gives 4/7
- So, 3/21 + 18/42 = 4/7
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