Add 21/42 and 15/18
21/42 + 15/18 is 4/3.
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,
15/18 = 15 × 7/18 × 7 = 105/126 - Add the two like fractions:
63/126 + 105/126 = 63 + 105/126 = 168/126 - 168/126 simplified gives 4/3
- So, 21/42 + 15/18 = 4/3
In mixed form: 11/3
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