Add 42/84 and 15/21
42/84 + 15/21 is 17/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
42/84 = 42 × 1/84 × 1 = 42/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
15/21 = 15 × 4/21 × 4 = 60/84 - Add the two like fractions:
42/84 + 60/84 = 42 + 60/84 = 102/84 - 102/84 simplified gives 17/14
- So, 42/84 + 15/21 = 17/14
In mixed form: 13/14
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