Answer:
4(31x^2+7)
Step-by-step explanation:
Answer: The required ratio is 1:1.
Step-by-step explanation:
Let the total number of CDs be 100
of CDs is given by

According to question,
of her Jazz CDs represents
of all her CDs.
Let the number of Jazz CDs be x
So, it becomes

So, Number of Jazz's CDs is 50
Number of Jazz non CDs is given by

Ratio of her CDs to her non- CDs is given by

Hence, the required ratio is 1:1.
Number of ways to select 3 books from 13 books for adoption is 286 .
<u>Step-by-step explanation:</u>
A Permutation is an ordered Combination. When the order does matter it is a Permutation. There are basically two types of permutation:
- Repetition is Allowed: such as the lock above. It could be "333".
- No Repetition: for example the first three people in a running race. You can't be first and second.
Formula is given by:
, where n is the number of things to choose from, and we choose r of them, no repetitions, order matters. Here , n=13 , r=3.
⇒ 
⇒ 
⇒ 
⇒ 
⇒ 
∴ Number of ways to select 3 books from 13 books for adoption is 286 .