Answer:
The difference between combinations and permutations is that in permutations, the order matters, while it doesn't with combinations. For example, if you are given 5 numbers (1,2,3,4,5) and you have to determine how many 3 digit numbers you can make, that is a permutation question because 123, 231, 321, etc. are all different numbers. If, for example, we have to find how many ways three people can be chosen out of a group of 5, that is a combination question and you must use the combination formula as the order of the three people does not matter. Other than the order, combinations and permutations are the same
Answer:
40 students
Step-by-step explanation:
We need a system of equations to find x or the students in advance:
2x + 4y = 800
x + y = 220
We can use substitution and isolate y in the second equation, which gives us y = 220 - x.
When we plug this into the first equation, we get 2x + 4(220 - x) = 800 and solving for x gives us x = 40.
Answer:
Step-by-step explanation:
find the slope 1/2
then write it as y-4=1/2(x+6)
then u get y=1/2x+7
Answer:
x = 2
Step-by-step explanation:
Given
4x - 3 = - 9 + 7x ( subtract 7x from both sides )
- 3x - 3 = - 9 ( add 3 to both sides )
- 3x = - 6 ( divide both sides by - 3 )
x = 2
