The first answer is B: 2 1/2
4 5/6 is put there twice except the last one is subtracting so you can put, 4 5/6 - 4 5/6 = 0 therefore the only number left is 2 1/2
the second one I really don't know sorry:(
The third answer is C because the cases come in 24. But they didn't tell you how many case she brought so the variable has to be by 24 and they took 43 which is the subtracting factor. So the answer is C.
And I also don't know the last one again sorry:(
Answer:
x^2-12x+27
Step-by-step explanation:
(x-3)(x-9)=x^2-3x-9x+27=x^2-12x+27
60/ (30/100)
= 60* (100/30)
= 200
The final answer is 200~
There are 720 ways through which 3 numbers can be selected from 10 numbers to open a keypad lock.
Given that there are 10 numbers are 3 numbers are required to open a keypad lock.
Permutations are the number of ways in which objects can be selected without replacements to form subsets.
It is expressed as n
=n!/(n-r)!.
Factorial of a number is the product of consecutive numbers less than the number.
Total numbers available=10
Numbers to be selected=3
Number of ways can be found by using permutations.
Number of ways =10
=10!/(10-3)!
=10!/7!
=10*9*8*7!/7!
=10*9*8
=720 ways.
Hence there are 720 ways through which 3 numbers can be selected from 10 numbers.
Learn more about permutations at brainly.com/question/1216161
#SPJ1