Since this is a combination not a permutation problem, (order does not matter) you should use the "n choose k" formula.
C=n!/(k!(n-k)!) where C is the number of unique combinations, n equals the total number of possible choices and k equals the specific number of choices. In this case:
C=9!/(4!(9-4)!)
C=9!/(4!5!)
C=362880/(24*120)
C=362880/2880
C=126
So there are 126 unique ways to pick 4 people from a group of 9 people.
When answering this question, I'm assuming "18 down" means 18 gallons
To find the answer, we can divide:
40/18 = 5
( This basically means that there are 5 containers in the 40 gallon container)
knowing this:
45*5 = 225
(Basically solves the time to fill 5 containers)
It will take 225 seconds
The given equation is
And we have to solve for y.
Solving for y, means isolating y . And to isolate y, we need to get rid of 4 that is with y .
It means we have to separate 4 from y, and for separation , we have to perform division. That is, we have to divide both sides by 4, and that will be the next step .
So out of the four options, correct option is the last option .
Answer:
x = 4, y = 2
Step-by-step explanation:
Start by multiplying the first equation by 2:
2x + 2y = 12 --> 4x + 4y = 24
Subtract the second from the first:
4x + 4y = 24
- 5x + 4y = 28
4x - 5x = -x
4y = 4y = 0
24 - 28 = -4
so you end with -x + 0 = -4
Solve for x to get x = 4
Plug x = 4 back into 2x + 2y = 12 to find y.
2(4) + 2y = 12
8 + 2y = 12
2y = 4
y = 2
Answer:
It is 11 and 4/7 I am pretty sure hope I helped!
