<h3>Answer:</h3>
There are 40,320 ways, in which 8 books can be arranged on a shelf.
<h3>Solution:</h3>
Here, we are to find the number of ways in which 8 books can be arranged on a shelf. The total number of books is 8 and the way of arranging books is also 8.
- If one book is placed in the first place, then 7 books will be placed in front of it. If 2 books are placed in the 2nd place, then only 6 books can be placed after that book. This sequence will continue till 1 .
<u>Permutations </u><u>:</u>
- A permutation is an arrangement of objects in a definite order.
➲<u> P ( n, r )= n ! / ( n - r ) !</u>
- n = total number of objects
- r = number of objects selected
The number of ways to arrange 8 books on a shelf will be :
➝ P ( n, r ) = n ! / ( n - r ) !
➝ P ( n, r ) = 8 ! / ( 8 - 8 ) !
➝ P ( n, r ) = 8 ! / 0 !
➝ P ( n, r ) = 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1 / 1
➝ P ( n, r ) = 40, 320
ㅤㅤㅤㅤㅤㅤ~ Hence, there are <u>40,320 ways</u> in which 8 books can be arranged on a shelf !
Sorry I thought I was gonna understand but I don’t but good luck:) you can do it
Answer:
A. 10.4 mph
Step-by-step explanation:
26÷2.5=10.4
Double checking your answer:
If she does 10.4 miles in an hour, she can get 20.8 in two hours
then you add half of how much she can go in an hour which is 5.2 (10.4÷2)
you add it together, and you will get 26 miles in total
(20.8+5.2=26)
-4x/5≥1/10
-8x≥1
x≤-1/8
x∈(-∞;-1/8]