Answer: 1692
Step-by-step explanation:
Formula to find the sample size :

Given : Confidence level : 
⇒ significance level =
z-value for 90% confidence interval (using z-table)=
Prior estimate of the population proportion (p) of customers who keep up with regular vehicle maintenance is unknown.
Let we take p= 0.5
Margin of error : E= 2%=0.02
Now, the required sample size will be :

Simplify , we get

Hence, the required sample size = 1692
Answer:
4/1
Step-by-step explanation:
this is because it is 4x
Children’s tickets are $4, adult tickets are $14
Explanation:
4a+6c=80
If they made $4 more dollars on the second day than the first by selling one extra child ticket then we know a child’s ticket is $4 per ticket.
4a+6*4=80
4a+24=80
4a=56
14=a
So each adult ticket costs $14.
You can check by filling in $14 and $4 for each equation.
4*14+6*4=80
4*14+7*4=84
Answer:
B
Step-by-step explanation: