Answer:
compound interest
Step-by-step explanation:
The interest charged on the principal for the entire loan term is known as Simple Interest. The interest computed on both principal and the previously earned interest is known as Compound Interest. Compound Interest gives a high return as compared to Simple Interest.
I think a and c. I really don’t know tho
Solution :
Given :

1. Cumulative distribution function




![$=\frac{1}{450}\left[\frac{x^3}{3}-\frac{x^2}{2}\right]_6^x$](https://tex.z-dn.net/?f=%24%3D%5Cfrac%7B1%7D%7B450%7D%5Cleft%5B%5Cfrac%7Bx%5E3%7D%7B3%7D-%5Cfrac%7Bx%5E2%7D%7B2%7D%5Cright%5D_6%5Ex%24)
![$=\frac{1}{450}\left[ \left( \frac{x^3}{3} - \frac{x^2}{2}\left) - \left( \frac{6^3}{3} - \frac{6^2}{2} \right) \right] $](https://tex.z-dn.net/?f=%24%3D%5Cfrac%7B1%7D%7B450%7D%5Cleft%5B%20%5Cleft%28%20%5Cfrac%7Bx%5E3%7D%7B3%7D%20-%20%5Cfrac%7Bx%5E2%7D%7B2%7D%5Cleft%29%20-%20%5Cleft%28%20%5Cfrac%7B6%5E3%7D%7B3%7D%20-%20%5Cfrac%7B6%5E2%7D%7B2%7D%20%5Cright%29%20%5Cright%5D%20%20%24)
![$=\frac{1}{450}\left[\frac{x^3}{3} - \frac{x^2}{2} - 54 \right]$](https://tex.z-dn.net/?f=%24%3D%5Cfrac%7B1%7D%7B450%7D%5Cleft%5B%5Cfrac%7Bx%5E3%7D%7B3%7D%20-%20%5Cfrac%7Bx%5E2%7D%7B2%7D%20-%2054%20%5Cright%5D%24)
2. Mean 


![$=\frac{1}{450} \left[\frac{x^4}{4} - \frac{x^3}{3} \right]_6^{12} \ dx$](https://tex.z-dn.net/?f=%24%3D%5Cfrac%7B1%7D%7B450%7D%20%5Cleft%5B%5Cfrac%7Bx%5E4%7D%7B4%7D%20-%20%5Cfrac%7Bx%5E3%7D%7B3%7D%20%5Cright%5D_6%5E%7B12%7D%20%5C%20dx%24)

![$=\frac{1}{450} [4608 - 252]$](https://tex.z-dn.net/?f=%24%3D%5Cfrac%7B1%7D%7B450%7D%20%5B4608%20-%20252%5D%24)
= 17.2857
Answer:
the required number of telephone orders to complete the 400 interviews is 3433
Step-by-step explanation:
Given the data in the question;
Let us represent the telephone numbers the researcher orders to complete the 400 interviews with Y.
Thus, The working phone numbers = 70% × Y
Now, number of ATM users = 45% × The working ph0ne numbers
⇒ 45% × ( 70% × Y )
number of ATM users = 0.45 × 0.70 × Y = 0.315Y
Thus; Number of people contacted that agrees to complete the survey will be;
⇒ 37% × number of ATM users
⇒ 0.37 × 0.315Y = 0.11655Y
so, since the researcher needs at least 400 interviews
Hence;
0.11655Y ≥ 400
Y ≥ 400 / 0.11655
Y ≥ 3432.0034 ≈ 3433
Therefore, the required number of telephone orders to complete the 400 interviews is 3433