Answer:
B and C work. A and D do not.
Step-by-step explanation:
This is one of those questions that you have to go through each answer to see what the results are. You don't have to go far to eliminate A and D so let's do that first.
A]
5n + 6
Let n = 1
5(1) + 6
5 + 6= 11
However there is trouble beginning with n = 2
5*2 + 6
10 + 6
16 All you need is one wrong answer and the choice is toast. So A won't work.
================
Try D
6(n - 1)+ 5
n=0
6*(-1) + 5
-6 + 5
- 1
And D has been eliminated with just 1 attempt. n= 2 or n = 1 would be even worse. D is not one of the answers.
=============
B
Let n = 1
6(1) + 5
6 + 5
11 The first term works.
n = 2
6*(2) + 5
12 + 5
17 and n = 2 works as well. Just in case it is hard to believe, let's try n = 3 because so far, everything is fine.
n = 3
6*(3) + 5
18 + 5
23 And this also works. I'll let you deal with n = 4
========
C
n = 0
6(0 + 1) + 5
6*1 + 5
6 + 5
11
n = 1
6(1 + 1) + 5
6*2 + 5
12 + 5
17 which works.
So C is an answer.
Let
where we assume |r| < 1. Multiplying on both sides by r gives
and subtracting this from 
gives
As n → ∞, the exponential term will converge to 0, and the partial sums will converge to
Now, we're given
We must have |r| < 1 since both sums converge, so
Solving for r by substitution, we have
Recalling the difference of squares identity, we have
We've already confirmed r ≠ 1, so we can simplify this to
It follows that
and so the sum we want is
which doesn't appear to be either of the given answer choices. Are you sure there isn't a typo somewhere?
Answer:
picture?
Step-by-step explanation:
The best way to solve this problem is with a simple equation: part = percent (in decimal form) x whole
In this problem, we're trying to solve for the <em>whole </em>amount that the camera can hold, so we'll assign that the variable w.
We can use the information they gave us - 96 is the <em>part</em>, and 24% is the percent. We'll convert that to decimal form - 0.24
Then, we just plug these values back into the above equation:
96 = 0.24w
Divide both sides by 0.24 to get w on it's own, and you have your answer!
400 = w
Therefore, the memory card can hold up to 400 pictures.
Note: this equation is <em>super </em>helpful. It's good to have on hand for any problem involving percents, because you can solve for the part, percent, or whole depending on the problem.
Answer:
a= 200
b = 210
Step-by-step explanation:
My assumption is, we have to find the length of sides of rectangle
Given
perimeter = 2a + 2b = 820 ft (i) (here a is smaller side and b is larger side)
area = a*b = 42,000 ft^2 (ii)
from eq (1)
2a + 2b = 820
=> 2(a+b) = 820
=> a+b = 820/2
=> a + b = 410
=> a = 410-b (iii)
putting the value of a in eq(ii), we get
(410-b) *b = 42,000
410b - b^2 = 42,000
0 = b^2 - 410b + 42000
b^2 - 410b + 42000 = 0
b^2- 200b- 210b + 42000 = 0
b(b-200)-210(b-200) = 0
(b-200)(b-210) = 0
or
b= 210 and b = 200
if b is larger side than b =210
By putting value of b in eq(iii),
a = 410 -210 = 200
