Evaluate (2 a + b)^2/(3 b - 1) where a = -2 and b = 5:
(2 a + b)^2/(3 b - 1) = (5 - 2×2)^2/(3×5 - 1)
3×5 = 15:
(5 - 2×2)^2/(15 - 1)
| 1 | 5
- | | 1
| 1 | 4:
(5 - 2×2)^2/14
2 (-2) = -4:
(-4 + 5)^2/14
5 - 4 = 1:
1^2/14
1^2 = 1:
Answer: 1/14
Answer:
(
4
,−
13
)
Step-by-step explanation:
Answer:
C. 3.4
Step-by-step explanation:
We need to find expected value, which is essentially the value that we expect to get based on the amount of each "thing" at hand.
Here, we have 4 multiple-choice questions worth 3 points each and 2 true/false questions worth 1 point each. Each multiple-choice question has 5 possible answers, so the probability that you get that multiple-choice question correct is 1/5. Similarly, each true/false question has 2 possible answers, so the probability that you get that question right is 1/2.
Expected value, denoted by E(x), has the formula:
E(x) = ∑ xp(x), where x is the number of points you get per problem here and p(x) is the probability of getting the problem correct
E(x) = 4 * 3 * (1/5) + 2 * 1 * (1/2) = 12/5 + 1 = 17/5 = 3.4.
The answer is thus C.
