Abag contains 25 tickets, each colored either red or yellow. red tickets are worth $0.50, and yellow tickets are worth $5.00. if the expected value of a ticket drawn at random from this bag is $3.20, how many of the tickets are red? the answer to the question is 10, i just need an explanation why.

10 red tickets

Step-by-step explanation:

Let us call x the number of red tickets.  

Notice since there are 25 tickets in the bag then we have 25-x yellow tickets.

Now, the probability of drawing a red ticket would be:

And the probability of drawing a yellow ticket would be:

Then we multiply each probability by their values and sum up to get the expected value, so that we get the equation:

We solve it like this:

Multiply both sides by 25 to clear of fractions:

Distribute:

Combine like terms:

Subtract 125 from both sides:

Divide both sides by -4.5

There are 10 red tickets in the bag.

y = - 6

step-by-step explanation:

given the point (- 2, y) lies on the graph then it is a solution of it's equation.

substitute x = - 2 into the equation for value of y

y = 3(- 2) = 3 × - 2 = - 6

the point on the graph is (- 2, 6)

b

step-by-step explanation: