Add 21/70 and 28/81
21/70 + 28/81 is 523/810.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 81 is 5670
Next, find the equivalent fraction of both fractional numbers with denominator 5670 - For the 1st fraction, since 70 × 81 = 5670,
21/70 = 21 × 81/70 × 81 = 1701/5670 - Likewise, for the 2nd fraction, since 81 × 70 = 5670,
28/81 = 28 × 70/81 × 70 = 1960/5670 - Add the two like fractions:
1701/5670 + 1960/5670 = 1701 + 1960/5670 = 3661/5670 - 3661/5670 simplified gives 523/810
- So, 21/70 + 28/81 = 523/810
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