Add 21/42 and 25/18
1st number: 21/42, 2nd number: 1 7/18
21/42 + 25/18 is 17/9.
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,
25/18 = 25 × 7/18 × 7 = 175/126 - Add the two like fractions:
63/126 + 175/126 = 63 + 175/126 = 238/126 - 238/126 simplified gives 17/9
- So, 21/42 + 25/18 = 17/9
In mixed form: 18/9
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