It'd be easier to do #18 if y ou were to break it up:
14* (first term + 14th term)
Sum from n=1 to 14 of n = S = ---------------------------------
14 2
14(1+14)
= ---------------- = 7(15) = 105
2
The sum of twice that is 210. The sum of "1 from n=1 to n=14" is just 14.
The final sum is 210 + 14 = 224 (answer)
Set up the equation like 4b+61=0, subtract 61 from both sides, and that'll be 4b=-61. Divide both sides by 4. b=15.25
Answer:
Step-by-step explanation:
We are given the following in the question:
Let P be the number of professor and S be the student in a college.
According to the question:
There are 19 times as many students as professors.
We have to write an equation to show the given relationship between professors and students.

The above situation is the situation that represents the given relationship.