Answer:
a) 
b) 
And replacing we got:

c) 


And adding we got:

Step-by-step explanation:
Previous concepts
The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".
Solution to the problem
Let X the random variable of interest, on this case we now that:
The probability mass function for the Binomial distribution is given as:
Where (nCx) means combinatory and it's given by this formula:
Assuming the following questions:
a. exactly five
For this case we can use the probability mass function and we got:

b. at least one
For this case we want this probability:

And we can use the complement rule and we got:


And replacing we got:

c. between four and six, inclusive.
For this case we want this probability:




And adding we got:

Answer:
the sum of exterior angles of a polygon is 360°
Step-by-step explanation:
a = original number of adult tickets
c = original number of child tickets
a/c = 2/5
a = 2c/5
(a+70)/(c+300) = 1/3
(2c/5 + 70)/(c + 300) = 1/3
2c/5 + 70 = (c + 300)/3
2c + 350 = 5(c + 300)/3
6c + 1050 = 5(c + 300) = 5c + 1500
c = 450
a = 2c/5 = 2×450/5 = 2×90 = 180
Joshua sold therefore in total
180 + 70 = 250 adult tickets.
and by the way
450 + 300 = 750 child tickets.
The reasonable estimate of the current customer price index is 195. The option B is the correct option.
<h3>Customer price index</h3>
Customer price index is the price index which measures the weight average of price of basket of customers goods or services.
It can be given as,

Here
is the cost of market basket in current period and
is the cost of market basket in the base period.
Cost of market basket in current period is

Cost of market basket in 1983 is,

Substitute all the values in the formula

Thus the value of current CPI is 168.5 which is near about the 170.
Hence, the reasonable estimate of the current customer price index is 195. The option B is the correct option.
Learn more about the customer price index here;
brainly.com/question/25495502