Add 15/21 and 28/70
15/21 + 28/70 is 39/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
15/21 = 15 × 10/21 × 10 = 150/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
28/70 = 28 × 3/70 × 3 = 84/210 - Add the two like fractions:
150/210 + 84/210 = 150 + 84/210 = 234/210 - 234/210 simplified gives 39/35
- So, 15/21 + 28/70 = 39/35
In mixed form: 14/35
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