Answer:
$210
Step-by-step explanation:
The first thing we can do is to add the $25 back on to the total cost.
25 + 115 = 140.
We do this because he Sam used a gift certificate on the ski's that are already 2/3 of the original price.
Now, to find the original price we can use this equation:

X represents the original price.
To solve this equation you would flip 2/3 to 3/2 and multiply that by 140, as seen below:

Now you can solve:

We can check this answer by multiplying 210 by 2/3
(210)(2/3) = 140
Remember, Sam used a gift certificate for $25
140 - 25 = $115
Therefore, the original price of the skis is $210.
<em>I hope this helps!!</em>
<em>- Kay :)</em>
Answer: a. 0.6759 b. 0.3752 c. 0.1480
Step-by-step explanation:
Given : The long-distance calls made by the employees of a company are normally distributed with a mean of 6.3 minutes and a standard deviation of 2.2 minutes
i.e.
minutes
minutes
Let x be the long-distance call length.
a. The probability that a call lasts between 5 and 10 minutes will be :-

b. The probability that a call lasts more than 7 minutes. :
![P(X>7)=P(\dfrac{X-\mu}{\sigma}>\dfrac{7-6.3}{2.2})\\\\=P(Z>0.318)\ \ \ \ [z=\dfrac{X-\mu}{\sigma}]\\\\=1-P(Z](https://tex.z-dn.net/?f=P%28X%3E7%29%3DP%28%5Cdfrac%7BX-%5Cmu%7D%7B%5Csigma%7D%3E%5Cdfrac%7B7-6.3%7D%7B2.2%7D%29%5C%5C%5C%5C%3DP%28Z%3E0.318%29%5C%20%5C%20%5C%20%5C%20%5Bz%3D%5Cdfrac%7BX-%5Cmu%7D%7B%5Csigma%7D%5D%5C%5C%5C%5C%3D1-P%28Z%3C0.318%29%5C%5C%5C%5C%3D1-0.6248%5C%20%5C%20%5C%20%5C%20%5B%5Ctext%7Bby%20z-table%7D%5D%5C%5C%5C%5C%3D0.3752)
c. The probability that a call lasts more than 4 minutes. :

Answer:
Step-by-step explanation:
t2/t1=r
-10/2=-5
2*-5=-10
Answer:
Step-by-step explanation: