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3 years ago

Find the sum of the geometric sequence –3, 15, –75, 375, … when there are 9 terms and select the correct answer below.

Mathematics

2 answers:

Lemur [1.5K]3 years ago

4 0

Answer:

Answer: A. -976563

Step-by-step explanation:

Sn=sum of the n terms of the geometric sequence.

a= the first term

r=the common ratio

n=numbers of terms.

Sn=a[(1-r^n)/(1-r)]

In this case:

a=-3

r=a₂/a₁=15/-3=-5

n=9

S₉=-3[(1-(-5)⁹) / (1-(-5))=

S₉=-3(1+1953125)/6)=

S₉=-3(1953126/6)=

S₉=-3(325521)

S₉=-976563

zavuch27 [327]3 years ago

3 0

Sn=sum of the n terms of the geometric sequence.
a= the first term
r=the common ratio
n=numbers of terms.

Sn=a[(1-r^n)/(1-r)]

In this case:
a=-3
r=a₂/a₁=15/-3=-5
n=9

S₉=-3[(1-(-5)⁹) / (1-(-5))=
S₉=-3(1+1953125)/6)=
S₉=-3(1953126/6)=
S₉=-3(325521)
S₉=-976563

Answer: A. -976563

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Not sure how to solve this one

Alex73 [517]

Answer:

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Step-by-step explanation:

In the given right triangle,

Measure of angle = x°

Opposite side of the angle = 12 units

Adjacent side of the angle = 6 units

By taking tangent ratio of the given angle,

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Answer:

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3 years ago

Variable y varies directly with variable x, and y = 5 when x = 8.

qaws [65]

Y = kx

Plug in what we know:

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Read 2 more answers

genetic experiment with peas resulted in one sample of offspring that consisted of green peas and yellow peas. a. Construct a %

Andreas93 [3]

Complete Question

A genetic experiment with peas resulted in one sample of offspring that consisted of 432 green peas and 164 yellow peas. a. Construct a 95% confidence interval to estimate of the percentage of yellow peas. b. It was expected that 25% of the offspring peas would be yellow. Given that the percentage of offspring yellow peas is not 25%, do the results contradict expectations?

Answer:

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