y= 1.25x+6.75
Make 31.75 y because that is the total cost he paid.
1.25x+6.75=31.75
1.25x=25
x=20
So he had 20 refills.
Substitute the value of x in equation 2. Then you'll get y=3. Then again substitute the value of y in x=1+y, you'll get x=4
Answer:
The probability that Joe's stock will go up and he will win in the lottery is 0.00005.
Step-by-step explanation:
Let the events be denoted as:
<em>X</em> = the stock goes up
<em>Y</em> = Joe wins the lottery
Given:
P (X) = 0.50
P (Y) = 0.0001
The events of the stock going up is not dependent on the the event of Joe winning the lottery.
So the events <em>X</em> and <em>Y</em> are independent of each other.
Independent events are those events that can occur together at the same time.
The joint probability of two independent events <em>A</em> and <em>B </em>is,

Compute the value of P (<em>X ∩ Y</em>) as follows:

Thus, the probability that Joe's stock will go up and he will win in the lottery is 0.00005.
See the attached picture.
The negative sign in front of the 2 makes the graph an upside down U shape.
3000th is the answer.
If I get it wrong, I apologize. I didn't exactly understand your grammar..