Add 21/70 and 70/81
21/70 + 70/81 is 943/810.
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,
70/81 = 70 × 70/81 × 70 = 4900/5670 - Add the two like fractions:
1701/5670 + 4900/5670 = 1701 + 4900/5670 = 6601/5670 - 6601/5670 simplified gives 943/810
- So, 21/70 + 70/81 = 943/810
In mixed form: 1133/810
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