Add 42/84 and 90/15
1st number: 42/84, 2nd number: 6 0/15
42/84 + 90/15 is 13/2.
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,
90/15 = 90 × 28/15 × 28 = 2520/420 - Add the two like fractions:
210/420 + 2520/420 = 210 + 2520/420 = 2730/420 - 2730/420 simplified gives 13/2
- So, 42/84 + 90/15 = 13/2
In mixed form: 61/2
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