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:
the tree will be 11.04 feet tall
Step-by-step explanation:
4 x 0.22 (22%) = 0.88
every year it grows 0.88 foot.
0.88 x 8 = 7.04
4 + 7.04 = 11.04 feet tall
sorry if this is wrong!
Step-by-step explanation:
(40-10)/7
The maximum amount of money she wants to spend is $40
Her adult ticket costs $10
She will pay for the children’s tickets with the remaining money
Each child’s ticket costs $7
To find the number of children she can take we need to use this expression (40-10)/7
Mrs Herñàndez can take 4 children
Answer:
120 liters of 60% alcohol solution is needed
Step-by-step explanation:
Let's assume
x liters of 60% alcohol solution is added
so, we get solution as
we are given
40 liters of a 20% alcohol solution is
so, total alcohol solution is
now, we can find total solutions
total solutions is
now, it is making 50% solution
so, we get
now, we can solve for x
So,
120 liters of 60% alcohol solution is needed
