Answer: 0.0668
Step-by-step explanation:
Given: Mean : 
Standard deviation : 
The formula to calculate z-score is given by :_
For x= 4 minutes , we have
The P-value = 
Hence, the probability that on a given run, the time will be 4 minutes or less = 0.0668
Answer:
A and B
Step-by-step explanation:
I tried it and it was correct. The United states has the tallest... and China has more buildings... are the correct ones.
Answer:
See below
Step-by-step explanation:
a) <u>Using the first two lines to get the equation:</u>
Since t = 0 represents a start point, the y-intercept is 163488
<u>Slope is:</u>
- (168392 - 163488)/10 = 490.4
<u>And the equation:</u>
- P(t) = 490.4(t - 1970) + 163488
b) Prediction of the population in 2012 using the function:
- P(2012) = 490.4(2012 - 1970) + 163488 = 184084.8
As we see the number we got is less than the one on the line 3 of the table. So the model underestimated the actual population.
Choose one of the equations, then try and rewrite in terms of 1 Unknown, eg I've chosen XZ= 22 and am going to write it in terms of X
XZ = 22
Z = 22/X (this is writing Z in terms of X)
So... X(22/X)= 22
22/X=22X
22 = 22X^2 (* ^2 is to the power 2)
Therefore X = 1
And Z= 22
Use this to solve the remaining equations
1xY = 4n + 3
22Y= 2n - 7
Then rearrange and do simultaneous equations
22Y - 66 = 88n
22Y + 7 = 2n
-73 = 86n
n = -73/86
It is very very likely that I have made a mistake somewhere here given the strange number I have for n but I spent far too long on this not to post it ahaha, even if the numbers are incorrect this is the general method I would follow
