A can do a piece of work in 20 days and B can do it in 12 days,B work for 9 days,in how many days A alone can do the work

What is the equation that represents the sequence in this problem ? Find the price after the 8th month

AVprozaik [17]

ANSWER

$\begin{gathered} a_n=ar^{n\text{ - 1}} \\ a_8\text{ = \$38.26} \end{gathered}$

EXPLANATION

The problem represents a geometric progression.

The general form of a geometric sequence is:

$a_n=ar^{n\text{ - 1}}$

where a = first term

r = common ratio

The first term from the table is the first price (for the first month). That is $80.00

To find the common ratio, we divide a term by its preceeding term.

Let us divide the price of the second month from the first.

We have:

$\begin{gathered} r\text{ = }\frac{72}{80} \\ r\text{ = 0.9} \end{gathered}$

The price after the 8th month is the value of a(n) when n = 8

So, we have that:

$\begin{gathered} a_8\text{ = 80 }\cdot0.9^{(8\text{ - 1)}} \\ a_8\text{ = 80 }\cdot0.9^7 \\ a_8\text{ = \$38.26} \end{gathered}$

5 0

9 months ago

Suppose a railroad rail is 3 kilometers and it expands on a hot day by 15 centimeters in length. Approximately how many meters w

earnstyle [38]

Answer:

Answer: 13.4 m

Step-by-step explanation:

For small angles, x, in radians,

tan(x) ≈ sin(x) = x

Use this to create an approximate diagram for the problem as shown in the figure below.

The actual deflected shape is parabolic, but it is approximated by an isosceles triangle with small equal angles.

The extend length is 3 km + 12 cm, which is

3000 + 0.12 = 3000.12 m

Half of the extended length is 1500.06 m

Let h+ the rise of the center of the rail above ground.

From the Pythagorean theorem, obtain

h² + 1500² = 1500.6²

h² = 1500.06² - 1500² = 180.004

h = 13.4 m, which is about 0.9% of the original length.

Read more on Brainly.com - brainly.com/question/5596356#readmore

6 0

2 years ago

I need an answer asap please, it’s the last question

swat32

$8
2 pizzas = $24
5 drinks = $10
$6 tip
24+10+6 = 40
Since it’s 5 friends, divide by 5
40/5 = 8
Each person pays $8

7 0

3 years ago

James says that 5/5 is greater than 9/10 is he correct please explain so that it is not confusing

astraxan [27]

Yes, James is correct.

Think of a pizza. If there are 5 slices and you have all 5 of them, then you have the whole pizza.

Now, instead of the pizza having 5 slices, it now has 10. Since the pizza is still the same size, the pieces are going to smaller. If you have 9 slices out of the 10, you won't have the whole pizza.

This is why 5/5 is greater than 9/10.

4 0

3 years ago

At 3:00 PM a man 138 cm tall casts a shadow 149 cm long. At the same time, a tall building nearby casts a shadow 163 m long. How

Andre45 [30]

The building is 151 meters tall

<h3>How to determine the height of the building?</h3>

From the question, we have the following parameters about the building and the man

Man's height = 138 cm

Man's shadow = 149 cm

Building's shadow = 163 m

Based on the above parameters, we have the following equivalent ratio:

Ratio = Height : Shadow

So, we have:

Man's height : Man's shadow = Building's height : Building's shadow

Substitute the known values in the above equation

138 cm : 149 cm = Building's height : 163 m

Remove the units

138 : 149 = Building's height : 163

Express as fraction

138 /149 = Building's height/163

Multiply both sides by 163

Building's height = 163 * 138 /149

Evaluate the product

Building's height = 151 m

Hence, the building is 151 meters tall

So, the complete parameters are:

Man's height = 138 cm

Man's shadow = 149 cm

Building's shadow = 163 m

Building's height = 151 m

A can do a piece of work in 20 days and B can do it in 12 days,B work for 9 days,in how many days A alone can do the work​

A can do a piece of work in 20 days and B can do it in 12 days,B work for 9 days,in how many days A alone can do the work