Add 84/15 and 20/42
1st number: 5 9/15, 2nd number: 20/42
84/15 + 20/42 is 638/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 15 × 14 = 210,
84/15 = 84 × 14/15 × 14 = 1176/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
20/42 = 20 × 5/42 × 5 = 100/210 - Add the two like fractions:
1176/210 + 100/210 = 1176 + 100/210 = 1276/210 - 1276/210 simplified gives 638/105
- So, 84/15 + 20/42 = 638/105
In mixed form: 68/105
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