salina is one-quarter of her aunts age if a represents her aunts age which expression represents her age
1 answer:
You might be interested in
Answer:
(a) The probability that proportion of heads is between 0.30 and 0.70 is 1.
(b) The probability that proportion of heads is between 0.40 and 0.65 is 0.9759.
Step-by-step explanation:
Let <em>X</em> = number of heads.
The probability that a head occurs in a toss of a coin is, <em>p</em> = 0.50.
The coin was tossed <em>n</em> = 100 times.
A random toss's result is independent of the other tosses.
The random variable <em>X</em> follows a Binomial distribution with parameters n = 100 and <em>p</em> = 0.50.
But the sample selected is too large and the probability of success is 0.50.
So a Normal approximation to binomial can be applied to approximate the distribution of <em> </em>(sample proportion of <em>X</em>) if the following conditions are satisfied:
- np ≥ 10
- n(1 - p) ≥ 10
Check the conditions as follows:
Thus, a Normal approximation to binomial can be applied.
So,
(a)
Compute the probability that proportion of heads is between 0.30 and 0.70 as follows:
Thus, the probability that proportion of heads is between 0.30 and 0.70 is 1.
(b)
Compute the probability that proportion of heads is between 0.40 and 0.65 as follows:
Thus, the probability that proportion of heads is between 0.40 and 0.65 is 0.9759.
If the three integers are , then we have
We can combine the fractions on the left side:
Answer:
0.6
Step-by-step explanation:
Given: Mean= $750
Standard deviation= $60
First, lets find out z-score of the interval between $624 and $768.
z score=
z score=
∴ z score for $624 is -2.1
Now, finding z score for $768
Z score=
∴ z score for $768 is 0.3
As per the z score table, the value for -2.1 is 0.0179 and for 0.3 is 0.6179
Now, subtracting the value to get proportion
∴ There are 0.6 proportion of laptops are in the range of $624 and $768