Add 18/20 and 42/84
18/20 + 42/84 is 7/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
18/20 = 18 × 21/20 × 21 = 378/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
42/84 = 42 × 5/84 × 5 = 210/420 - Add the two like fractions:
378/420 + 210/420 = 378 + 210/420 = 588/420 - 588/420 simplified gives 7/5
- So, 18/20 + 42/84 = 7/5
In mixed form: 12/5
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