Try to understand this. Hope this help. Answer for 2 only.
Answer:
The estimate of a population proportion is approximately 541.
Step-by-step explanation:
We can solve the the problem by using the formula for minimum sample needed for interval estimate of a population proportion which is given by the formula
n = pq ((Z/2) / E)^2
As, p is not defined so we use the standard p and q which is 0.5 and 0.5.
The reason for this is we have to choose form 0.1 to 0.9 both values of p and q, we will find the maximum value of pq occurs when they both are 0.5.
Next, we will find the value of (Z/2) by looking at the Z-table, we will find that at 98% confidence (Z/2) = 2.326. Now we start substituting the values in the above formula
n = (0.5)×(0.5) × (2.326/0.05)^2
n = 541.027
n ≅ 541.
It increases the mean value of the prizes.
Answer:
-2a³+9a²+45a+6ab²+18b²
Step-by-step explanation:
(a+3)(-2a²+15a+6b²)
Distribute the a:
-2a³+15a²+6ab²
Then distribute the 3:
-6a²+45a+18b²
Now add both of the results together:
-2a³+15a²+6ab²-6a²+45a+18b²
Combine like terms:
-2a³+9a²+45a+6ab²+18b²
