Add 18/84 and 21/42
18/84 + 21/42 is 5/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
18/84 = 18 × 1/84 × 1 = 18/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Add the two like fractions:
18/84 + 42/84 = 18 + 42/84 = 60/84 - 60/84 simplified gives 5/7
- So, 18/84 + 21/42 = 5/7
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