First you need to find a common denominator. To do that, you have to look at the denominators of the two fractions. They are 6 and 4. The closest number that they can both go into is 12. 6x2=12, 4x3=12. Then, what you multiplied the denominator by to get the number 12, you have to multiply the numerator, too.
So, it would be 8/12 + 6/12. That is 14/12, or 1 1/6. Then you add that to the whole numbers, 6 and 4, which is 10. 10 + 1 1/6= 11 1/6.
The answer is 11 1/6
So sorry that took so long
The most important is to interpret (understand) the question.
You are asked to find the probability that the first roll is an even number and the second roll is not 2.
The joint probability is the product of both probabilities.
1) Probability that the first roll is even:
Three outcomes out of 6 are even: 3/6 = 1/2
2) Probability that the second roll is not 2.
Five outcomes out of 6 are no 2: 5/6
3) Joint probability = 1/2 * 5/6 = 5/12
Answer: 5/12
I would say that in doing an experiment that will have multiple trials, if one of the variables is changed each time, say temperature or pressure amount, then average results between experiments will not be valid. They would only be valid if the same conditions applied for each one, to determine the inherent variability of the result.