Add 21/42 and 9/21
21/42 + 9/21 is 13/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
21/42 = 21 × 1/42 × 1 = 21/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
9/21 = 9 × 2/21 × 2 = 18/42 - Add the two like fractions:
21/42 + 18/42 = 21 + 18/42 = 39/42 - 39/42 simplified gives 13/14
- So, 21/42 + 9/21 = 13/14
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