Answer:
C,B,D,A
Step-by-step explanation:
Start at 3(X) and move based on the question
So we are given the mean and the s.d.. The mean is 100 and the sd is 15 and we are trying the select a random person who has an I.Q. of over 126. So our first step is to use our z-score equation:
z = x - mean/s.d.
where x is our I.Q. we are looking for
So we plug in our numbers and we get:
126-100/15 = 1.73333
Next we look at our z-score table for our P-value and I got 0.9582
Since we are looking for a person who has an I.Q. higher than 126, we do 1 - P. So we get
1 - 0.9582 = 0.0418
Since they are asking for the probability, we multiply our P-value by 100, and we get
0.0418 * 100 = 4.18%
And our answer is
4.18% that a randomly selected person has an I.Q. above 126
Hopes this helps!
Answer: (x,y) = (-1, 1)
This means that x = -1 and y = 1
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Explanation:
The first equation says that y is the same as 2x+3
That allows us to substitute y for 2x+3 in the second equation like so:
2x+5y = 3
2x+5( y ) = 3
2x + 5(2x+3) = 3 .... y replaced with 2x+3
2x+10x+15 = 3
12x+15 = 3
12x = 3-15
12x = -12
x = -12/12
x = -1
Then we'll substitute this into the first equation to find y
y = 2x+3
y = 2(-1) + 3 .... x replaced with -1
y = -2+3
y = 1
Together x = -1 and y = 1 pair up to form the ordered pair solution (x,y) = (-1,1)
If you were to graph y = 2x+3 and 2x+5y=3 on the same xy grid, then you should see that the two lines intersect at the location (-1,1). This is a visual way to determine the solution quickly through use of a graphing calculator.
Answer:
$2.50
Step-by-step explanation:
Shelley buys one pack of gum for $1
Price of gum: $1
Total amount of money spent: $1.00
Shelley buys another pack of gum for $0.50 more
1 + 0.50 = 1.5
Price of gum: $1.50
Total amount of money spent: $2.50
