You can use the properties of logarithm to get to the solution.
The approximate value for given term is given by

<h3>What is logarithm and some of its useful properties?</h3>
When you raise a number with an exponent, there comes a result.
Lets say you get

Then, you can write 'b' in terms of 'a' and 'c' using logarithm as follows

Some properties of logarithm are:

<h3>Using the above properties</h3>

Thus,
The approximate value for given term is given by

Learn more about logarithm here:
brainly.com/question/20835449
Answer:
a) 7.79%
b) 67.03%
c) Cumulative Distribution Function

Step-by-step explanation:
We are given the following in the question:

where x is the duration of a call, in minutes.
a) P( calls last between 2 and 3 minutes)
![=\displaystyle\int^3_2 p(x)~ dx\\\\= \displaystyle\int^3_20.1e^{-0.1x}~dx\\\\=\Big[-e^{-0.1x}\Big]^3_2\\\\=-\Big[e^{-0.3}-e^{-0.2}\Big]\\\\= 0.0779\\=7.79\%](https://tex.z-dn.net/?f=%3D%5Cdisplaystyle%5Cint%5E3_2%20p%28x%29~%20dx%5C%5C%5C%5C%3D%20%5Cdisplaystyle%5Cint%5E3_20.1e%5E%7B-0.1x%7D~dx%5C%5C%5C%5C%3D%5CBig%5B-e%5E%7B-0.1x%7D%5CBig%5D%5E3_2%5C%5C%5C%5C%3D-%5CBig%5Be%5E%7B-0.3%7D-e%5E%7B-0.2%7D%5CBig%5D%5C%5C%5C%5C%3D%200.0779%5C%5C%3D7.79%5C%25)
b) P(calls last 4 minutes or more)
![=\displaystyle\int^{\infty}_4 p(x)~ dx\\\\= \displaystyle\int^{\infty}_40.1e^{-0.1x}~dx\\\\=\Big[-e^{-0.1x}\Big]^{\infty}_4\\\\=-\Big[e^{\infty}-e^{-0.4}\Big]\\\\=-(0- 0.6703)\\= 0.6703\\=67.03\%](https://tex.z-dn.net/?f=%3D%5Cdisplaystyle%5Cint%5E%7B%5Cinfty%7D_4%20p%28x%29~%20dx%5C%5C%5C%5C%3D%20%5Cdisplaystyle%5Cint%5E%7B%5Cinfty%7D_40.1e%5E%7B-0.1x%7D~dx%5C%5C%5C%5C%3D%5CBig%5B-e%5E%7B-0.1x%7D%5CBig%5D%5E%7B%5Cinfty%7D_4%5C%5C%5C%5C%3D-%5CBig%5Be%5E%7B%5Cinfty%7D-e%5E%7B-0.4%7D%5CBig%5D%5C%5C%5C%5C%3D-%280-%090.6703%29%5C%5C%3D%200.6703%5C%5C%3D67.03%5C%25)
c) cumulative distribution function

For a triangle 30-60-90,
If shorter leg is x, then hypotenuse is 2x.
So, if shorter leg is 4,
then hypotenuse is 2*4 = 8.
Answer is 8.
Answer:
d = 25
Step-by-step explanation:
Perhaps you want to solve for d:
(0.3d -1.5)/(3 1/3) = 0.84/(7/15)
Change the division by a fraction to multiplication by its inverse.
(0.3d -1.5)·(3/10) = (0.84)·(15/7)
0.09d -0.45 = 1.8 . . . . . . . . . . . . simplify
d - 5 = 20 . . . . . . . . . . . . . . . . . . divide by 0.09
d = 25 . . . . . . . . . . . . . . . . . . . . . add 5
_____
Grouping symbols help show what is being divided by what. Especially where mixed numbers are involved, parentheses help show that the number 3 1/3 is not supposed to be interpreted as the product of 3 and 1/3.