1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Sedbober [7]
3 years ago
15

A study of peach trees found that the average number of peaches per tree was 725. The standard deviation of the population is 70

peaches per tree. A scientist wishes to find the 95% confidence interval for the mean number of peaches per tree. How many trees does she need to sample to obtain an average accurate to within 10 peaches per tree
Mathematics
1 answer:
TEA [102]3 years ago
3 0

Answer:

She needs to sample 189 trees.

Step-by-step explanation:

We have that to find our \alpha level, that is the subtraction of 1 by the confidence interval divided by 2. So:

\alpha = \frac{1 - 0.95}{2} = 0.025

Now, we have to find z in the Ztable as such z has a pvalue of 1 - \alpha.

That is z with a pvalue of 1 - 0.025 = 0.975, so Z = 1.96.

Now, find the margin of error M as such

M = z\frac{\sigma}{\sqrt{n}}

In which \sigma is the standard deviation of the population and n is the size of the sample.

The standard deviation of the population is 70 peaches per tree.

This means that \sigma = 70

How many trees does she need to sample to obtain an average accurate to within 10 peaches per tree?

She needs to sample n trees.

n is found when M = 10. So

M = z\frac{\sigma}{\sqrt{n}}

10 = 1.96\frac{70}{\sqrt{n}}

10\sqrt{n} = 1.96*70

Dividing both sides by 10:

\sqrt{n} = 1.96*7

(\sqrt{n})^2 = (1.96*7)^2

n = 188.2

Rounding up:

She needs to sample 189 trees.

You might be interested in
A 20 foot ladder is resting against the side of the house the base of the latter is 4 feet away from the house approximately how
notka56 [123]

The ladder resting against the house forms a triangle similar to the one in the image below

To answer this question you must use Pythagorean theorem

a^{2} +b^{2}=c^{2}

a and b are the legs (the sides that form a perpendicular/right angle)

c is the hypotenuse (the side opposite the right angle)

In this case...

a = x

b = 4

c = 20

^^^Plug these numbers into the theorem

x^{2} +4^{2} =20^{2}

solve for x

x^{2} + 16 = 400

x^{2} = 384

x = 8√6

or

x ≈ 19.5959....

Hope this helped!

~Just a girl in love with Shawn Mendes

5 0
3 years ago
Jack said that if you take a number and multiply it by a fraction, the product will always be smaller than what you started with
ELEN [110]

Answer:

Is not correct. The product not always will be smaller.

Step-by-step explanation:

A fraction could increase a number if you multiply it.  

If the numerator is higher to the  denominator,  it will increase it.  

If the numerator is smaller to the  denominator,  it will decrease it.

<u>For example,</u>

10 x 4/3

For fraction multiplication, multiply the numerators and then multiply the denominators to get

10×4/1×3=40/3= 13,33

13,33 is higher than 10.

5 x 10/3

For fraction multiplication, multiply the numerators and then multiply the denominators to get

5×10/1×3=50/3

16,66 is higher than 5.

5 0
3 years ago
How many students travel more than 3 miles to school? ​
suter [353]
12..................
6 0
3 years ago
There are 5 blue
Minchanka [31]

Answer:

The probability of randomly picking a red candy is 1/20 and In percentage value 5%

Step-by-step explanation:

There are 5 blue candies, 6 red candies, and 9 yellow candies.

Now, Total

5 + 6 + 9 = 20 candies

Now, The probability of randomly picking a red candy is 1/20

Now, In percentage

1/20 × 100% = 5%

Thus, The probability of randomly picking a red candy is 1/20 and In percentage value 5%.

<u>-TheUnknownScientist</u>

5 0
2 years ago
Evaluate the algebraic expressions for the given value of each variable
baherus [9]
Plug in 4 for r and 1 for s

r+s^2
4+1^2

Evaluate exponents first (order of operations)
4+1

Add
5

Final answer: 5
4 0
3 years ago
Other questions:
  • What is the coefficient of x^3y^2 in the expansion of (2x+y)^5
    13·2 answers
  • In attempting to become financially organized, a person:
    10·2 answers
  • How do you solve he formulas for numbers 9 and 10?
    13·1 answer
  • A bakery wants to determine how many trays of doughnuts it should prepare each day. Demand is normal with a mean of 5 trays and
    11·1 answer
  • Estimate how many times larger 4 x 10^15 is than 8 x 10^9 in the form of a single digit times an integer power of 10.
    10·1 answer
  • Solve the expression, 3-3x6+2.
    6·2 answers
  • What is the missing exponent of 32=2?
    15·2 answers
  • The graph shows which inequality? The equation of the boundary line is y = –x + 4. y –x + 4 y ≥ –x + 4
    14·1 answer
  • Frida applied the steps below to find the product of (–1.2)(–9.4). Step 1: (–1.2)(–9.4) = (–9.4)(–1.2) Step 2: = (–9.4)(–1) + (–
    10·3 answers
  • Write the equation of the line passing through points (2,-2) and (1,0) in the slope intercept form​
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!