Answer:
A) 99.7% of people have an IQ between 64 and 136.
B) 5% of people have an IQ score less than 76 or greater than 124.
C) 16% of people have an IQ score greater than 112.
Step-by-step explanation:
The Empirical Rule tells us that, in a normal or 'bell-shaped' distribution, 68% of the data is one standard deviation from the mean, 95% of the data is two standard deviations from the mean, and 99.7% of the data is three standard deviations from the mean.
A) 64 and 136 are 3 standard deviations away from the mean, so 99.7% of people have an IQ between 64 and 136.
B) 76 and 124 are 2 standard devations away from the mean, but the answer is asking what percentage is not between them. 100% - 95% gives us 5%.
C) 112 is one standard deviation away from the mean. If we want to find the percentage greater, then we can do 100% - 50% (as 112 is to the left of the mean), then we can take half of 68 to get 34%, and after subtracting 50% and 34% from the 100%, we get 16%.
Answer:
25
Step-by-step explanation:
We require to solve for n, hence
n(n + 1) = 325
multiply both sides by 2 to eliminate the fraction
n(n + 1) = 650
n² + n = 650
subtract 650 from both sides to have equation in standard form
n² + n - 650 = 0 ← in standard form
(n + 26)(n - 25) = 0 ← in factored form
equate each factor to zero and solve for n
n + 26 = 0 ⇒ n = - 26
n - 25 = 0 ⇒ n = 25
however, n > 0 ⇒ n = 25
Answer:
n = -5
Step-by-step explanation:
n - 4 = 3n + 6
n = 3n + 10
-2n = 10
n = -5
Answer
The owner lose is $100 .
Reason
As given
A man comes into a store and steals $100 from the register without the owner knowledge.
Comes back and buys $70 worth of stuff and the owner gives him $30 in change.
i.e First man steals $100 than give back to owner when he buys $70 worth of stuff and the owner gives him $30 in change.
Therefore the total owner lose is the sum of $70 worth of stuff and $30 in change.
Total owner lose = $70 + $30
= $100
Therefore the owner lose be $100 .
Hence proved
L=2W+3, A=LW, using L from the first in the second gives you:
A=(2W+3)W
A=2W^2+3W, and we are told A=90 so
2W^2+3W=90
2W^2+3W-90=0
2W^2-12W+15W-90=0
2W(W-6)+15(W-6)=0
(2W+15)(W-6)=0, since W>0 for all real possibilities,
W=6ft, and since L=2W+3
L=15ft
So the pool will be 6 ft wide by 15 ft long.
