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2 years ago

Find the 9th partial sum of the geometric sequence an=43n–1.

Mathematics

1 answer:

siniylev [52]2 years ago

7 0

Answer:

39364.

Step-by-step explanation:

I guess its an = 4*(3)^(n-1)

r = 3, a1 = 4 and n = 9

Sum of n terms = a1 * (r^n - 1) / (r - 1)

so S9 = 4 *(3^9 - 1) / (3 - 1)

= 4 * (19683 - 1) / 2

= 78728/2

= 39364.

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I need this to be explained and have the answer thanks I AM BEGGING YOU!!!!!!!!!!!!

Firdavs [7]

Answer:

Store A has a better deal because $402.90 is less than $404.10.

Step-by-step explanation:

Store A

The $25 off coupon reduces the price to ...

$499 - 25 = $474

The discount from this amount is 15%, so is ...

$474 × 0.15 = $71.10

The final amount paid is then ...

$474.00 -71.10 = $402.90

(Side note: you can select the correct answer at this point, because only one answer shows this value.)

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Store B

After the $20 off coupon, the price is ...

$469 -20 = $449

The additional 10% discount amounts to ...

$449 × 0.10 = $44.90

So, the final price is ...

$449.00 -44.90 = $404.10

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Now, you know that Store A offers the better price because $402.90 is less than $404.10.

6 0

3 years ago

In which months were the expenses greater than the income? Name the month and find how much money was lost.

Liono4ka [1.6K]

expenses is greater in Jan and Feb

Jan −85.6 Loss

Feb −162.44 Loss

Mar 0

June 306.77 Gain

July 301.5 Gain

Aug 337.88 Gain

5 0

3 years ago

Read 2 more answers

Johnny makes $8.25 an hour working at the local restaurant. His paycheck shows that he works 29.5 hours over the past week. How

svetlana [45]

To do this you can do (pay) x (hours) to work out how much Johnny makes for example:

8.25 x 29.5 = 243.375$ so the answer is 243.375$

4 0

3 years ago

Read 2 more answers

Shelly and Steve buy prepaid phone

muminat

Answer:

Steve

Step-by-step explanation:

steve is buying 200 minutes which is more than 150 minutes

Hope i helped :) :) :)

5 0

3 years ago

In ΔXYZ, ∠Y=90° and ∠X=73°. ∠ZWY=80° and XW=80. Find the length of ZY to the nearest 100th.

lawyer [7]

Answer:

Solution given:

Y=90°

∠X=73°.

∠ZWY=80°

and XW=80.

ZY=?

We know that

In right angled triangle ∆ XYZ

Tan 73= $\frac{p}{h}$

3.27= $\frac{yz}{xy}$

3.27×[xy]=yz

xw+wy= $\frac{yz}{3.27}$

wy= $\frac{yz}{3.27}$ -80...........(1)

again

In right angled triangle WYZ

Tan 80= $\frac{yz}{wy}$

5.67×wy=yz

wy= $\frac{yz}{5.67}$

yz=5.67×wy............................................(2)

Equating equation 1&2

$\frac{yz}{5.67}$ = $\frac{yz}{3.27}$ -80

$\frac{yz}{3.27}$ - $\frac{yz}{5.67}$ =80

5.67yz-3.27yz=80*5.67*3.27

2.4yz =1483.272

yz= $\frac{1483.272}{2.4}$

yz=618.03

:.y=618.03unit.the length of ZY to the nearest 100th is 618.

8 0

3 years ago