Step-by-step explanation:
in a geometric sequence there is a constant factor x that is multiplied with every previous term to create the next one.
a2 = 20
a5 = 1280 = a2×x×x×x = a2×x³ = 20x³
64 = x³
x = 4
=> a1 = 5
therefore
an = an-1×4 =
n > 1
Pi(
) is the ratio of circumference to diameter for any circle.
Perimeter is the distance around a circle.
Circumference of circle 
.
Perimeter of circle 
What is circle ?
A circle is a spherical shape without boundaries or edges.
A circle is a closed, curved object with two dimensions in geometry.
Consider two small arcs AB and CD of two circles of radii x and y units, both of which make an angle of measure θ at the centers P and Q respectively.
For smaller values of θ, the arc length AB is almost equal to the length of the line segment 
. Similarly, arc CD ≅ 
.
Using the SAS rule of triangle similarity, we can say that APB and CQD are similar triangles because their angles are the same and their ratios are AP: PB = CQ: QD = 1: 1. So, it stands to reason that AB: AP = CD: CQ.
Circumference = 
diameter or circumference = 2 radius if this constant equals some value.
So it was proved.
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<span><span>1,867,866,560</span><span>1,867,866,560</span></span><span>.</span>
Complete question :
It is estimated 28% of all adults in United States invest in stocks and that 85% of U.S. adults have investments in fixed income instruments (savings accounts, bonds, etc.). It is also estimated that 26% of U.S. adults have investments in both stocks and fixed income instruments. (a) What is the probability that a randomly chosen stock investor also invests in fixed income instruments? Round your answer to decimal places. (b) What is the probability that a randomly chosen U.S. adult invests in stocks, given that s/he invests in fixed income instruments?
Answer:
0.929 ; 0.306
Step-by-step explanation:
Using the information:
P(stock) = P(s) = 28% = 0.28
P(fixed income) = P(f) = 0.85
P(stock and fixed income) = p(SnF) = 26%
a) What is the probability that a randomly chosen stock investor also invests in fixed income instruments? Round your answer to decimal places.
P(F|S) = p(FnS) / p(s)
= 0.26 / 0.28
= 0.9285
= 0.929
(b) What is the probability that a randomly chosen U.S. adult invests in stocks, given that s/he invests in fixed income instruments?
P(s|f) = p(SnF) / p(f)
P(S|F) = 0.26 / 0.85 = 0.3058823
P(S¦F) = 0.306 (to 3 decimal places)
The rate at which the sound travels in km/hr is 0.142km/hr
<h3>Conversion of m/s to km/hr</h3>
If a sound wave travels with a speed of 5120m/s, in order to convert to km/he, we will use the conversion factor below;
1hr = 3600secs
1km = 1000m
Using the conversion factor in our dimensional analysis
5120m/s = 5120m/1s * 1km/1000m * 3600s/1hr
5120m/s = 5120m/3600000
5120m/s = 0.142km/hr
Hence the rate at which the sound travels in km/hr is 0.142km/hr
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