john had 21.00After buying 2 notebooks he had 13.00
21-13= 8 / 2 =4 each notebook cost 4 dollars.
Answer:
i) P(X<33) = 0.9232
ii) P(X>26) = 0.001
Step-by-step explanation:
<u><em>Step(i):-</em></u>
Given that the mean of the Population = 30
Given that the standard deviation of the Population = 4
Let 'X' be the Normal distribution
<u>Step(ii):-</u>
i)
Given that the random variable X = 33
>0
P(X<33) = P( Z<1.5)
= 1- P(Z>1.5)
= 1 - ( 0.5 - A(1.5))
= 0.5 + 0.4232
P(X<33) = 0.9232
<u>Step(iii) :-</u>
Given that the random variable X = 26
>0
P(X>26) = P( Z>3.5)
= 0.5 - A(3.5)
= 0.5 - 0.4990
= 0.001
P(X>26) = 0.001
The equation for a line is y=mx+b. where m is the slope and b is the y intercept.
The slope of 17 is provided. This means m=17. The point (0,0) tells you the y intercept is 0. This means b=0
Plugging these into the equation and simplifying:
y=17x+0
y=17x
Hope this helps :)
Answer:
I should use at least 304 students
Step-by-step explanation:
Margin error (E) = t × sd/√n
E = 40
sd = 300
confidence level (C) = 98% = 0.98
significance level = 1 - C = 1 - 0.98 = 0.02 = 2%
t-value corresponding to 2% significance level and infinity degree of freedom is 2.326
n = (t×sd/E)^2 = (2.326×300/40)^2 = 17.445^2 = 304 (to the nearest integer)
Answer:
x=18
Step-by-step explanation:
We need to find the areas of the rectangles
1st rectangle
A= l*w
A = (2x+4)*9
= 18x+36
2nd rectangle
A = l*w
= 15*(3x-30)
= 45x-450
Since the area of the rectangles are equal, we set these two equations equal
18x+36 = 45x-450
Subtract 18x from each side
18x-18x+36 = 45x-18x-450
36 = 27x-450
Add 450 to each side
36+450 =27x
486 = 27x
Divide by 27 on each side
486/27 = 27x/27
18=x