Add 21/42 and 3/12
21/42 + 3/12 is 3/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 12 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 12 × 7 = 84,
3/12 = 3 × 7/12 × 7 = 21/84 - Add the two like fractions:
42/84 + 21/84 = 42 + 21/84 = 63/84 - 63/84 simplified gives 3/4
- So, 21/42 + 3/12 = 3/4
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