What is the sum of the n terms of the series 5 10 20 40 . . . ?

Mathematics

1 answer:

Lubov Fominskaja [6]2 years ago

5 0

Hello,

$5+10+20+40+...\\
=5(1+2+2^2+2^3+...+2^{n-1})\\
$
$=5*\frac{5^n-1}{4}$

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The probability that it will snow on the last day of January is 85%. If the probability remains the same of the first eight day

MrRa [10]

Answer:

Here, we have:

P(5 days snow in this 8 days) = 8C5 x (0.85)^5 x (1 - 0.85)^3 = 0.084

P(6 days snow in this 8 days) = 8C6 x (0.85)^6 x (1 - 0.85)^2 = 0.238

P(7 days snow in this 8 days) = 8C7 x (0.85)^7 x (1 - 0.85)^1 = 0.385

P(8 days snow in this 8 days) = 8C8 x (0.85)^8 x (1 - 0.85)^0 = 0.272

Add up those above, then the probability that it will snow AT LEAST five of those days in February:

P = 0.084+ 0.238 + 0. 385 + 0.272 = 0.979

Hope this helps!

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3 years ago

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Mashcka [7]

Answer:

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Step-by-step explanation:

1) To find and interval where any given function is increasing, the first derivative of its function must be greater than zero:

$f'(x)>0$

To find its decreasing interval :

$f'(x)$

2) Then let's find the critical point of this function:

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