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3 years ago

12

What is the sum of a common geometric series if the first term is 8 and the common ratio is 1/2?

1 answer:

stealth61 [152]3 years ago

6 0

Answer: A

Step-by-step explanation:

The sum to infinity of a geometric series is

S (∞ ) = \frac{a}{1-r} ( - 1 < r < 1 )

where a is the first term 8 and r is the common ratio, hence

S(∞ ) = {8}{1-\{1}{2} } = {8}{1}{2} } = 16

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A store sells flower arrangements at a cost of $28 each. Which statements are true regarding the price of the arrangements? Chec

Maru [420]

Let's check each case to determine the solution to the problem.

we know that

The cost of each flower arrangements is $\$28$

Statements

<u>case A)</u> If the price is marked down by $10$ percent, the new price will be $\$25.20$

we know that

If the price is marked down by $10$ percent

then

the new price will be

$10\%= \frac{10}{100} =0.10$

$(1-0.10)*\$28=0.90*\$28 \\= \$25.20$

$\$25.20=\$25.20$

therefore

The statement case A) is True

<u>case B)</u> If the price is marked down by $25$ percent, the new price will be $\$21$

we know that

If the price is marked down by $25$ percent

then

the new price will be

$25\%= \frac{25}{100} =0.25$

$(1-0.25)*\$28=0.75*\$28 \\= \$21$

$\$21=\$21$

therefore

The statement case B) is True

<u>case C)</u> If the price is marked down by $50$ percent, the new price will be $\$19$

we know that

If the price is marked down by $50$ percent

then

the new price will be

$50\%= \frac{50}{100} =0.50$

$(1-0.50)*\$28=0.50*\$28 \\= \$14$

$\$14 \neq \$19$

therefore

The statement case C) is False

<u>case D)</u> If the price is marked down by $35$ percent, the new price will be $\$18.20$

we know that

If the price is marked down by $35$ percent

then

the new price will be

$35\%= \frac{35}{100} =0.35$

$(1-0.35)*\$28=0.65*\$28 \\= \$18.20$

$\$18.20=\$18.20$

therefore

The statement case D) is True

<u>case E)</u> If the price is marked down by $40$ percent, the new price will be $\$29.80$

we know that

If the price is marked down by $40$ percent

then

the new price will be

$40\%= \frac{40}{100} =0.40$

$(1-0.40)*\$28=0.60*\$28 \\= \$16.80$

$\$16.80 \neq \$29.80$

therefore

The statement case E) is False

7 0

3 years ago

Read 2 more answers

How do you write 30.0 in scientific notation? ____× 10^_____

Pie

Answer:

It's written as

$3 \times {10}^{1}$

Hope this helps you

8 0

3 years ago

Read 2 more answers

In a square with side length of 6, what is the distance between the center of the square and the center of the largest equilater

Vanyuwa [196]

Place the right angle at the origin. Short leg on x-axis.
The forth corner of the square is the point on the hypotenuse where the line y = x intersects. (Draw a diagram!)
In this case the hypotenuse is y = -4x/3 + 8
x = -4x/3 + 8
7x/3 = 8
7x = 24
x = 3.428571429

8 0

3 years ago

A five-digit number starts with a number between 4-9 in the first position, with no restrictions on the remaining 4 digits. a

Maurinko [17]

Answer:

(a) $Pr = 0.3024$

(b) $Pr = 0.6976$

(c) $Pr = \frac{^9P_{n-1}}{10^{n-1}}$

Step-by-step explanation:

Given

$Start = \{5,6,7,8\}$ i.e. between 4 and 9

$n(Start) =4$

$Digits = 5$

Solving (a): Probability that each of the 5 digit are different

Since there is no restriction;

The total possible selection is as follows:

$First\ digit = 4$ (i.e. any of the 4 start digits)

$Second\ digit = 10\\$ (i.e. any of the 10 digits 0 - 9)

$Third\ digit = 10$ (i.e. any of the 10 digits 0 - 9)

$Fourth\ digit = 10$ (i.e. any of the 10 digits 0 - 9)

$Fifth\ digit = 10$ (i.e. any of the 10 digits 0 - 9)

So, the total is:

$Total = 4 * 10 * 10 * 10 * 10$

$Total = 40000$

For selection that all digits are different, the selection is:

$First\ digit = 4$ (i.e. any of the 4 start digits)

$Second\ digit = 9$ (i.e. any of the remaining 9)

$Third\ digit = 8$ (i.e. any of the remaining 8)

$Fourth\ digit = 7$ (i.e. any of the remaining 7)

$Fifth\ digit = 6$ (i.e. any of the remaining 6)

So:

$Selection =4 * 9 * 8 * 7 * 6$

$Selection =12096$

So, the probability is:

$Pr = \frac{Selection}{Total}$

$Pr = \frac{12096}{40000}$

$Pr = 0.3024$

Solving (b): At least 1 repeated digit

The probability calculated in (a) is the all digits are different i.e. P(None)

So, using laws of complement

We have:

$P(At\ least\ 1) = 1 - P(None)$

So, we have:

$Pr= 1 - 0.3024$

$Pr = 0.6976$

Solving (c): An expression to model the probability.

<em>Using (a) as a point of reference, we have;</em>

$Pr = \frac{Selection}{Total}$

Where

$Selection =4 * 9 * 8 * 7 * 6$ ---- for selection of 5 i.e. n = 5

$Total = 4 * 10 * 10 * 10 * 10$

$Selection =4 * 9 * 8 * 7 * 6$

This can be rewritten as:

$Selection = 4 * ^9P_4$

4 can be expressed as: 5 - 1

So, we have:

$Selection = (5-1) *^9P_{5-1}$

Substitute n for 5

$Selection = (n-1) *^9P_{n-1}$

$Selection = (n-1)^9P_{n-1}$

$Total = 4 * 10 * 10 * 10 * 10$

This can be rewritten as:

$Total = 4 * 10^4$

$Total = (5-1) * 10^{5-1}$

$Total = (n-1) * 10^{n-1}$

$Total = (n-1) 10^{n-1}$

So, the expression is:

$Pr = \frac{(n-1)^9P_{n-1}}{(n-1)10^{n-1}}$

$Pr = \frac{^9P_{n-1}}{10^{n-1}}$

<em>Where n represents the digit number</em>

5 0

3 years ago

Robin can run 1.71 kilometers in 10 minutes. How far can she run in 1.5 hours?

Flura [38]

Answer:

I think is 15.39 kilometers

Step-by-step explanation:

1 hour=60 minutes +.5 hours =90 minutes = 9 x 1.71 = 15.39

7 0

2 years ago