Add 9/21 and 20/42
9/21 + 20/42 is 19/21.
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,
9/21 = 9 × 2/21 × 2 = 18/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
20/42 = 20 × 1/42 × 1 = 20/42 - Add the two like fractions:
18/42 + 20/42 = 18 + 20/42 = 38/42 - 38/42 simplified gives 19/21
- So, 9/21 + 20/42 = 19/21
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