Add 21/42 and 18/28
21/42 + 18/28 is 8/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
18/28 = 18 × 3/28 × 3 = 54/84 - Add the two like fractions:
42/84 + 54/84 = 42 + 54/84 = 96/84 - 96/84 simplified gives 8/7
- So, 21/42 + 18/28 = 8/7
In mixed form: 11/7
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