B. (n + 15) x 3--- That seems to be the correct answer. I hope I helped!
Answer:
(5r - 20)
Step-by-step explanation:
(3r + 14) + (Ar + B) = (8r - 6)
B = -6 - 14 = -20
A = 8 - 3 = 5
Answer:
(x-9)(x²+9x+81); it'll give a difference of cubes
Step-by-step explanation:
Generally, the difference of cubes formula is (a³-b³)=(a-b)(a²+ab+b²), and the third option is the only one which fits it; with "a"= x and "b"= 9.
*The sum of cubes formula is (a³+b³)=(a+b)(a²-ab+b²); for future reference.
So we know that an average is the sum of the scores divided by the number of scores that were added together. In this case we are going to be dealing with 4 tests. So let's say x is the score for our fourth test. We can create this equation:

So then we need to simplify the top:

Then multiply by 4 on both sides to get rid of the denominator:

Then solve for x:

So now we know that Sam needs to score a 67 on the fourth test to have an average score of 50.
Answer:
Option b, c and e are wonderful approaches to solve the problem.
Step-by-step explanation:
Option (b) is appropriate this is because the option is talking about Simple random sampling where random universities are chosen to remove bias.
Option (c) is correct because this is an example of Stratified sampling where two homogenous groups (private and public universities are considered) and samples are chosen at random to remove bias
Option (e) is correct because this again is an example of Simple random sampling where 60 random STEM majors are chosen at random.