Add 21/28 and 12/42
21/28 + 12/42 is 29/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
21/28 = 21 × 3/28 × 3 = 63/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
12/42 = 12 × 2/42 × 2 = 24/84 - Add the two like fractions:
63/84 + 24/84 = 63 + 24/84 = 87/84 - 87/84 simplified gives 29/28
- So, 21/28 + 12/42 = 29/28
In mixed form: 11/28
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