Answer:
Step-by-step explanation:
Step-1 : Multiply the coefficient of the first term by the constant 2 • 2 = 4
Step-2 : Find two factors of 4 whose sum equals the coefficient of the middle term, which is 3 .
-4 + -1 = -5
-2 + -2 = -4
-1 + -4 = -5
1 + 4 = 5
2 + 2 = 4
4 + 1 = 5
Observation : No two such factors can be found !!
Answer:
0.61596
Step-by-step explanation:
Given that:
λ = 5 (5 errors per page)
Poisson distribution formula :
P(x = x) = (λ^x * e^-λ) / x!
Probability that page does not need to be retyped means that error on page is less than or equal to 5
P(x ≤ 5) = p(x = 5) + p(x = 4) +... + p(x = 0)
The individual probabilities can be obtained using the formula above or the use of a calculator
P(x ≤ 5) = 0.17547 + 0.17547 + 0.14037 + 0.08422 + 0.03369 + 0.00674
P(x ≤ 5) = 0.61596
The normal distribution curve for the problem is shown below
We need to standardise the value X=405.5 by using the formula


We now need to find the probability of z=0.32 by reading the z-table
Note that z-table would give the reading to the left of z-score, so if your aim is to work out the area to the right of a z-score, then you'd need to do:

from the z-table, the reading

gives 0.6255
hence,

The probability that the mean weight for a sample of 40 trout exceeds 405.5 gram is 0.3475 = 34.75%
Since the ratio of sides is 4 to 3, the proportion is:

x =
9
Try 4 because a die has six sides and 6-2=4