Which of the following is a continuous random variable? a. The number of goals scored in a hockey game
b. The number of correct answers on a multiple-choice test
c. The heights of children in a preschool
d. The number of houses for sale in a city

The correct answer is:

c) The heights of children in a preschool

Step-by-step explanation:

Continuous variables are variables that can take on any value in a measuring series and scale. There is no limit to the possibilities of the data in a continuous variable. In this example, the heights of children can take on an infinite number of values, it may be 0.5m, 0.43m, 0.33m, etc.

Discrete variables, on the other hand, are variables that are obtained by counting. There is a limit to the possibilities that the values in this category can take on. For example, when counting the number of goals in a hockey game, it can be 2 goals, 10 goals 20 goals, but you cannot count 15.5 goals or 22.2 goals, the number is a whole discrete number. Hence options a, b and d are discrete variables.

the polynomial is a perfect square trinomial of the form a^2-2ab+b^2:

option a. true

step-by-step explanation:

9x^2-12x+4

comparing with the form a^2-2ab+b^2

1.) a^2=9x^2

solving for a: square root both sides of the equation:

sqrt(a^2)=sqrt(9x^2)

a=sqrt(9) sqrt(x^2)

a=3x

2.) b^2=4

solving for b: square root both sides of the equation:

sqrt(b^2)=sqrt(4)

b=2

to be a perfet square trinomial 2ab must be equal to 12x. let's check:

2ab = 2 (3x) (2)

2ab = 12x

correct