Add 7/81 and 21/70
7/81 + 21/70 is 313/810.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 70 is 5670
Next, find the equivalent fraction of both fractional numbers with denominator 5670 - For the 1st fraction, since 81 × 70 = 5670,
7/81 = 7 × 70/81 × 70 = 490/5670 - Likewise, for the 2nd fraction, since 70 × 81 = 5670,
21/70 = 21 × 81/70 × 81 = 1701/5670 - Add the two like fractions:
490/5670 + 1701/5670 = 490 + 1701/5670 = 2191/5670 - 2191/5670 simplified gives 313/810
- So, 7/81 + 21/70 = 313/810
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