Add 70/81 and 45/20
1st number: 70/81, 2nd number: 2 5/20
70/81 + 45/20 is 1009/324.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 20 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 81 × 20 = 1620,
70/81 = 70 × 20/81 × 20 = 1400/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
45/20 = 45 × 81/20 × 81 = 3645/1620 - Add the two like fractions:
1400/1620 + 3645/1620 = 1400 + 3645/1620 = 5045/1620 - 5045/1620 simplified gives 1009/324
- So, 70/81 + 45/20 = 1009/324
In mixed form: 337/324
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