Add 21/42 and 7/9
21/42 + 7/9 is 23/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 9 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 9 × 14 = 126,
7/9 = 7 × 14/9 × 14 = 98/126 - Add the two like fractions:
63/126 + 98/126 = 63 + 98/126 = 161/126 - 161/126 simplified gives 23/18
- So, 21/42 + 7/9 = 23/18
In mixed form: 15/18
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