Add 20/70 and 21/81
20/70 + 21/81 is 103/189.
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,
20/70 = 20 × 81/70 × 81 = 1620/5670 - Likewise, for the 2nd fraction, since 81 × 70 = 5670,
21/81 = 21 × 70/81 × 70 = 1470/5670 - Add the two like fractions:
1620/5670 + 1470/5670 = 1620 + 1470/5670 = 3090/5670 - 3090/5670 simplified gives 103/189
- So, 20/70 + 21/81 = 103/189
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