Let's begin by listing out the information given to us:
There are four students: n = 4
Number of students to be selected: r = 2
To calculate the combination of 2 students to be chosen, we use:

Therefore, there 12 possible combinations from these
Answer:
- The sum of the series is given as
7/(1 + 7z)
- The series converges for (-1/7, 1/7)
Step-by-step explanation:
Given the geometric series:
7 - 14z + 28z² - 56z³ + ...
The common ratio r is given as
-14z/7 or 28z²/(-14z) or -56z³/(28z²) and so on
r = -7z
The sum of the series is given as
S = a/(1 - r)
Where a is the first term in the series.
S = 7/(1 -(-7z))
= 7/(1 + 7z)
The series converges for |-7z| < 1
That is for -1/7 < z < 1/7
Answer:

Step-by-step explanation:
First FOIL (n + 7)(n + 8) and then distribute n
(n + 7)(n + 8) = 
n (
)
= 
<u>Answer:</u>
The correct answer option is C. 1.
<u>Step-by-step explanation:</u>
We are to divide
by
.
Rewriting them as a fraction in whole:

Changing the division into multiplication by taking the reciprocal of the fraction in the denominator to get:
× 
Cancelling out the like terms to get:
1
Answer:
15 miles
Step-by-step explanation:
12 * 440 = 5280 (yards every day)
5280 * 5 = 26400 (yards per week)
26400 *0.000568182 = 15 miles