Answers:
x = -8/5 or x = 8/5
Sum of the first ten terms where all terms are positive = 4092
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Explanation:
r = common ratio
- first term = 4
- second term = (first term)*(common ratio) = 4r
- third term = (second term)*(common ratio) = (4r)*r = 4r^2
The first three terms are: 4, 4r, 4r^2
We're given that the sequence is: 4, 5x, 16
Therefore, we have these two equations
Solve the second equation for r and you should find that r = -2 or r = 2 are the only possible solutions. If r = -2, then 5x = 4r solves to x = -8/5. If r = 2, then 5x = 4r solves to x = 8/5.
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To find the sum of the first n terms, we use this geometric series formula
Sn = a*(1 - r^n)/(1 - r)
We have
- a = 4 = first term
- r = 2, since we want all the terms to be positive
- n = 10 = number of terms to sum up
So,
Sn = a*(1 - r^n)/(1 - r)
S10 = 4*(1 - 2^10)/(1 - 2)
S10 = 4*(1 - 1024)/(-1)
S10 = 4*(-1023)/(-1)
S10 = 4092
Answer:
So we reject the null hypothesis and accept the alternate hypothesis that rats learn slower with sound.
Step-by-step explanation:
In this data we have
Mean= u = 18
X= 38
Standard deviation = s= 6
1) We formulate the null and alternate hypothesis as
H0: u = 18 against Ha : u > 18 One tailed test .
2) The significance level alpha = ∝= 0.05 and Z alpha has a value ± 1.645 for one tailed test.
3)The test statistics used is
Z= X- u / s
z= 38-18/6= 3.333
4) The calculated value of z = 3.33 is greater than the z∝ = 1.645
5) So we reject the null hypothesis and accept the alternate hypothesis that rats learn slower with sound.
First we set the criteria for determining the true of value of the variable. That whether the rats learn in less or more than 18 trials.
Then we find the value of z for the given significance value given and the test about to be checked.
Then the test statistic is determined and calculated.
Then both value of z and z alpha re compared. If the test statistics falls in the rejection region reject the null hypothesis and conclude alternate hypothesis is true.
The figure shows that the calulated z value lies outside the given z values
Answer:
five times a number of pencils plus three pencils =twenty-eight pencils.
Step-by-step explanation:
x = 5, Have a great day!
Answer:
The required equation is : 5 · 4000 = 20,000
Step-by-step explanation:
We have to use multiple of 10 for at least one factor.
So, in order to form our equation, we take one factor as 4000 which is a multiple of 10 (10 × 400 = 4000)
And the other condition to form the equation is given that the product should contain 4 zeros, so we need to multiply the first factor 4000 by some number such that the product contains 4 zeros.
Therefore, if we multiply 4000 by 5 we get the product as 20000 which contains 4 zeros.
Hence, 5 × 4000 = 20,000 is our required equation.
4.
The ratio is 3/4 for corresponding dimensions, the ratio of their surface areas is equal to the square of this ratio:

Simplify the exponent:

Cross multiply:

Divide 9 to both sides:

So the surface area of the second solid is 54 square meters.
The ratio is 3/4 for corresponding dimensions, the ratio of their volumes is equal to the cube of this ratio:

Simplify the exponent:

Cross multiply:

Divide 64 to both sides:

5.
A globe is a sphere, use the formula for the volume of a sphere:

The radius is half of the diameter, so the radius here is 40/2 = 20. Plug it in the formula, use 3.14 to approximate for Pi:

Simplify the exponent:

Multiply: