Matthew is making a sequence in which -3 is added to each successive term. The 6th term in his sequence is -1. What is the 1st t
1 answer:
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Answer:
Step-by-step explanation:
Hello!
The objective is to test ESP, for this, a psychic was presented with cards face down and asked to determine if each of the cards was one of four symbols: a star, cross, circle, square.
Be X: number of times the psychic identifies the symbols on the cards correctly is a size n sample.
p the probability that the psychic identified the symbol on the cards correctly
You have to calculate the sample size n to estimate the proportion with a confidence level of 95% and a margin of error of d=0.01
The CI for the population proportion is constructed "sample proportion" ± "margin of error" Symbolically:
p' ±
Where is the margin of error. As you can see, the formula contains the sample proportion (it is normally symbolized p-hat, in this explanation I'll continue to symbolize it p'), you have to do the following consideration:
Every time the psychic has to identify a card he can make two choices:
"Success" he identifies the card correctly
"Failure" he does not identify the card correctly
If we assume that each symbol has the same probability of being chosen at random P(star)=P(cross)=P(circle)=P(square)= 1/4= 0.25
Let's say, for example, that the card has the star symbol.
The probability of identifying it correctly will be P(success)= P(star)= 1/4= 0.25
And the probability of not identifying it correctly will be P(failure)= P(cross) + P(circle) + P(square)= 1/4 + 1/4 + 1/4= 3/4= 0.75
So for this experiment, we'll assume the "worst case scenario" and use p'= 1/4 as the estimated probability of the psychic identifying the symbol on the card correctly.
The value of Z will be
Now using the formula you have to clear the sample size:
To estimate p with a margin of error of 0.01 and a 95% confidence level you have to take a sample of 7203 cards.
I hope this helps!
Answer:
Step-by-step explanation:
Width of the sign made by Darius initially = 2 feet
Length of the sign = 2 feet 6 inches
Dimension of the flyer are 10 inches by 8 inches. Since, in original sign the measure of length is greater, therefore, the length of flyer is 10 inches and its width is 8 inches.
In order to find the scale factor we must convert the lengths and widths to same units. Lets convert the length and width of sign into inches.
Since, 1 feet = 12 inches
Length of the sign = 2 feet 6 inches = 2(12) + 6 inches = 30 inches
Width of the sign = 2 feet = 2(12) inches = 24 inches
Now we can find the scale factor by either comparing the lengths or widths of both the designs. Scale factor will be equal to the ratio of corresponding lengths/widths.
So, the scale factor would be:
Length of Flyer : Length of Sign
= 10 inches : 30 inches
= 1 : 3
=
This shows, the length of flyer is times as that of the sign. So, the scale factor that Darius must use is
. The length and width of the flyer are
as that of the sign.
The same scale factor would result if we would have used the ratio of widths instead of the lengths.
Scale Factor = Width of Flyer : Width of sign
= 8 : 24
= 1 : 3
Therefore, Darius must type the scale factor of in his computer to get the size of the flyer.