The number of customers that enter a store during one day is an example of:

a. a continuous random variable

b. a discrete random variable

c. either a continuous or a discrete random variable, depending on the number of the customers

d. either a continuous or a discrete random variable, depending on the gender of the customers

b. a discrete random variable

Step-by-step explanation:

The number of customers that enter a store during a given day is a positive integer. That is, we do not expect fractional values for the random variables since the number of persons visiting the store must be integer rather than fractional. So the distribution of the random variable will be discrete in nature rather than continuous. Among the given options, option B satisfies this requirement.

75 tickets have been sold so far.

step-by-step explanation:

in this question it is clearly mentioned that 45 children's tickets have been sold and this number is 60% of the total tickets sold.

now let's assume the total number of tickets sold be x.

then 60% of x = 45

⇒

⇒ x(.6) = 45

by dividing with .6 on both the sides of the equation

⇒ x = 75

therefore 75 tickets have been sold so far.