Answer:
x= (y-5)/(-3)
Step-by-step explanation:
Answer:

Step-by-step explanation:
A set of normally distributed data has a mean of 3.2 and a standard deviation of 0.7. Find the probability of randomly selecting 30 values and obtaining an average greater than 3.6.
We can denote the population mean with the symbol 
According to the information given, the data have a population mean:
.
The standard deviation of the data is:
.
Then, from the data, a sample of size
is taken.
We want to obtain the probability that the sample mean is greater than 3.6
If we call
to the sample mean then, we seek to find:

To find this probability we find the Z statistic.

Where:
Where
is the standard deviation of the sample



Then:

The probability sought is: 
When looking in the standard normal probability tables for right tail we obtain:

Answer
44.1
Step-by-step explanation:
(-4.2)^2/2/5
17.64/2/5
44.1
First, let's define your variables!
x=cost of tickets for adults
y=cost of tickets for kids...
You know that they sold 900 tickets, which means the combination of x and y equals 900.
Therefore one equation is...
x+y=900
We also have to take care of the second equation...
We know that 13x represents the total cost of ADULT tickets
We know 7y represents the total cost for the children...
Which means...
13x+7y=11000
There are you equations! (bolded)