Add 20/21 and 28/70
20/21 + 28/70 is 142/105.
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,
20/21 = 20 × 10/21 × 10 = 200/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
28/70 = 28 × 3/70 × 3 = 84/210 - Add the two like fractions:
200/210 + 84/210 = 200 + 84/210 = 284/210 - 284/210 simplified gives 142/105
- So, 20/21 + 28/70 = 142/105
In mixed form: 137/105
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