A) For this problem, we will need to use a normal calculation, in that we find the z-score and the area to the right using Table A.
z = (10 - 7.65) / 1.45
z = 1.62
area to the left for a z-score of 1.62 = 0.9474
area to the right for a z-score of 1.62 = 0.0526
The probability that a randomly selected ornament will cost more than $10 is 0.0526 or 5.26%.
B) For this problem, we will use the binomial probability formula since the problem is asking for the probability that exactly 3 ornaments cost over $10. There are two forms of this equation. One is <em>nCr x p^r x q^n-r</em> and the other is <em>(n r) x p^r x (1 - p)^n-r</em>. I will show both formulas below.
8C3 x 0.0526^3 x 0.9474^5
(8 3) x 0.0526^3 x 0.9474^5
With both equations, the answer is the same. Whichever you are more familiar or comfortable with is the one I would recommend you use.
The probability that exactly 3 of the 8 ornaments cost over $10 is 0.00622 or 0.622%.
Hope this helps!! :)
Round 693,856,639 to the nearest thousand.How do you that than? Thats a long NUMBER?
Well, I'm going to tell you that if the number is higher than 5 than you round up but if the number is lower 5 you round down. So, how would you do that to find the nearest thousand? 693,856,639 so, you would know where the thousand is right? it's 6,639 lets just cancel the part 693,85 and think about 6,639. As I told you if the number is higher than 5 than you round up but if the number is lower 5 you round down.
6,639 so now if you look at the right side it's higher than 5 it's a 6 so, if you round up to the nearest thousand it's 7,000
so 6,639=7,000
