Answer:
The greater the sample size the better is the estimation. A large sample leads to a more accurate result.
Step-by-step explanation:
Consider the table representing the number of heads and tails for all the number of tosses:
Number of tosses n (HEADS) n (TAILS) Ratio
10 3 7 3 : 7
30 14 16 7 : 8
100 60 40 3 : 2
Compute probability of heads for the tosses as follows:

The probability of heads in case of 10 tosses of a coin is -0.20 away from 50/50.

The probability of heads in case of 30 tosses of a coin is -0.033 away from 50/50.

The probability of heads in case of 100 tosses of a coin is 0.10 away from 50/50.
As it can be seen from the above explanation, that as the sample size is increasing the distance between the expected and observed proportion is decreasing.
This happens because, the greater the sample size the better is the estimation. A large sample leads to a more accurate result.
1/2 yards times ) is 3, so 1/2 would be the answer.
Answer:
The number of nickels is 45 and the number of dimes is 72.
Step-by-step explanation:
Let
x ----> number of nickels
y ----> number of dimes
Remember that


so
------> equation A

------> equation B
<em>Solve the system by substitution</em>
we have
------> equation A
------> equation B
Multiply both equations by 100 both sides
---->
--> equation C
----> equation D
substitute equation C in equation D

solve for y




Find the value of x




<em>Alternative Method</em>
Solve the system by graphing
Remember that the solution is the intersection point both graphs
using a graphing tool
the solution is the point (45,72)
therefore
The number of nickels is 45 and the number of dimes is 72.
Answer:
And we can find this probability with the normal standard distirbution or excel and we got:
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the lenghts of a population, and for this case we know the distribution for X is given by:
Where
and
We are interested on this probability
And the best way to solve this problem is using the normal standard distribution and the z score given by:
If we apply this formula to our probability we got this:
And we can find this probability with the normal standard distirbution or excel and we got: