☁️ Answer ☁️
5. IS E (none of these)
Because I got:
-125y^5/162x
6. X = 5/3
Hope it helps.
Have a nice day noona/hyung.
Answer:
No, the on-time rate of 74% is not correct.
Solution:
As per the question:
Sample size, n = 60
The proportion of the population, P' = 74% = 0.74
q' = 1 - 0.74 = 0.26
We need to find the probability that out of 60 trains, 38 or lesser trains arrive on time.
Now,
The proportion of the given sample, p = 
Therefore, the probability is given by:
![P(p\leq 0.634) = [\frac{p - P'}{\sqrt{\frac{P'q'}{n}}}]\leq [\frac{0.634 - 0.74}{\sqrt{\frac{0.74\times 0.26}{60}}}]](https://tex.z-dn.net/?f=P%28p%5Cleq%200.634%29%20%3D%20%5B%5Cfrac%7Bp%20-%20P%27%7D%7B%5Csqrt%7B%5Cfrac%7BP%27q%27%7D%7Bn%7D%7D%7D%5D%5Cleq%20%5B%5Cfrac%7B0.634%20-%200.74%7D%7B%5Csqrt%7B%5Cfrac%7B0.74%5Ctimes%200.26%7D%7B60%7D%7D%7D%5D)
P![(p\leq 0.634) = P[z\leq -1.87188]](https://tex.z-dn.net/?f=%28p%5Cleq%200.634%29%20%3D%20P%5Bz%5Cleq%20-1.87188%5D)
P![(p\leq 0.634) = P[z\leq -1.87] = 0.0298](https://tex.z-dn.net/?f=%28p%5Cleq%200.634%29%20%3D%20P%5Bz%5Cleq%20-1.87%5D%20%3D%200.0298)
Therefore, Probability of the 38 or lesser trains out of 60 trains to be on time is 0.0298 or 2.98 %
Thus the on-time rate of 74% is incorrect.
Answer:
<u><em>For x - y = 2</em></u>
You need to find x or y in one of the equations and then substitute that into the other.
So we have;
x-y=2
4x-3y=11
We will take the first equation and find x;
x-y=2
add y to both sides;
x-y+y=2+y
x=2+y
Now we take that answer and substitute it forx in the other equation;
4(2+y)-3y=11
8+4y-3y=11
8+y=11
y=3
Now we have what y equals, so we use it in the first equation to find x;
x-3=2
x=5
So we have;
x=5; y=3
Hope you understand!
=)
<u><em>And for 4x – 3y = 11</em></u>
Multiply the first equation by 2 and the second by 3 so that there are the same number of y's in each:
8x - 6y = 22 ...(3)
30x + 6y = -3 ...(4)
Now add (3) and (4) term by term:
38x + 0 = 19
or
38x = 19
or x = 1/2
Put this back into equation (1)
4*(1/2) - 3y = 11
or
2 - 3y = 11
Subtract 2 from both sides:
-3y = 9
Divide both sides by -3
y = -3
In the step after -6x+10=4x+20, he moved the terms incorrectly. you have to add 6x to both sides so it would be 10=4x+6x+20 which simplifies to 10=10x+20. subtract 20 from both sides to get -10=10x. divide both sides by 10. the answer is x=-1
I am pretty sure it is linear decrease,