Add 42/84 and 18/15
1st number: 42/84, 2nd number: 1 3/15
42/84 + 18/15 is 17/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
42/84 = 42 × 5/84 × 5 = 210/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
18/15 = 18 × 28/15 × 28 = 504/420 - Add the two like fractions:
210/420 + 504/420 = 210 + 504/420 = 714/420 - 714/420 simplified gives 17/10
- So, 42/84 + 18/15 = 17/10
In mixed form: 17/10
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