Answer:
Step-by-step explanation:
Note: If you have any queries related the answer please do comment. I would be very happy to resolve all your queries.
Firstly we will make PMF
For X=0, P=(4/5)^3=64/125
For X=1, P=C(3,1)*(1/5)*(4/5)^2=3*16/125=48/125
For X=2, P=C(3,2)*(1/5)^2*(4/5)=3*4/125=12/125
For X=3, P=C(3,3)*(1/5)^3=1/125
So,
E[X^2]=1*48/125+2^2*(12/125)+3^2/125=0.84
E[X]=48/125+12/125*2+1/125*3=0.6
So,
E[X]^2=0.36
120
OA = OB
angle OAN = 90 degrees, so OAB and OBA is both 30 degrees.
First, convert the 25% to a real mathematical number. For percents, this is always done by dividing the 25% by 100%, or 25% / 100% = 0.250.
Second, find out what 25% of $100 is. This is the amount of the sale discount. This is always found by mulitplying 0.250 by the item's cost $100, like this:
0.250 x $100 = $25.00.
So for this sale, you'll save $25.00 on this item.
This means, the cost of the item to you is
$100 - $25.00 = $75.00.
Alternatively, you can think about it this way. The item is 25% off. This means you'll pay 75.000% of the total cost (100% - 25% = 75.000%).
Now what's 75.000% of the total cost?
0.750 x $100 = $75.00.
Just like the result above, the sale price on the item is $75.00.
Hope this helps you on your assignment! :)