Add 84/70 and 28/21
1st number: 1 14/70, 2nd number: 1 7/21
84/70 + 28/21 is 38/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
84/70 = 84 × 3/70 × 3 = 252/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
28/21 = 28 × 10/21 × 10 = 280/210 - Add the two like fractions:
252/210 + 280/210 = 252 + 280/210 = 532/210 - 532/210 simplified gives 38/15
- So, 84/70 + 28/21 = 38/15
In mixed form: 28/15
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