b. Find the probability of removing exactly 2 nickels, 2 dimes and 2 quarters.
Answer:
(a) 1 - (15 C 6) / (30 C 6)
(b) (5 C 2) x (10 C 2) x (15 C 2) / (30 C 2)
Step-by-step explanation:
Number of nickels = 5
Number of dimes = 10
Number of quarters = 15
(a) The probability of getting 6 quarters
= (15 C 6) / (30 C 6)
So, the probability of not getting 6 quarters = 1 - (15 C 6) / (30 C 6)
(b) Probability of getting 2 nickels , 2 dimes and 2 quarters
= (5 C 2) x (10 C 2) x (15 C 2) / (30 C 2)
Answer:
And we can find this probability using the complement rule:
And in order to find these probabilities we can use tables for the normal standard distribution, excel or a calculator.
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 lifetime of a certain type of battery 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 using the complement rule:
And in order to find these probabilities we can use tables for the normal standard distribution, excel or a calculator.
Answer:
75 ft
Step-by-step explanation:
Here we are given a right angled triangle with a known angle of 20°, length of the hypotenuse to be 80 and we are to find the length of the base x.
For that, we can use the formula for cosine for which we need an angle and the lengths of base and hypotenuse.
So putting in the given values to get:
Therefore, the value of x is the closest to 75 ft.
There are 9,000,000 seven-digit positive integers.
Explanation:
For the first digit, we have 9 choices: 1, 2, 3, 4, 5, 6, 7, 8, 9.
For each remaining digit, we have 10 choices: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.
Each choice is independent of the others. So, the number of total 7-digit positive integers is the product of all the numbers of choices for each digit.
hope it helps
need brainliest......
Since 0 cannot be put as the first digit, there are 9 choices for the first digit, and the next 6 digits have 10 choices. So, there are 9 × 10^6 = 9000,000 numbers.
What is the recursive rule that represents this situation?\
an=
a1=
Answer:
an = 65 + 5
a1 = 65
Step-by-step explanation:
If the begining value is 65, then a1 has to be itL
a1 = 65
Then, if this amount increased every minute then 5 has to be added to this value each time:
an = 65 + 5
But this means that 5 is added to 65 every time with no increase, so the five must me multiplied by the n value:
an = 65 + 5
a2 = 65 + 10 = 75
But this value should be 70 because it is the first point after 65 so it should be +5 not +10
To do this we can simply subtract one from the n value that is being multiplied by 5:
an = 65 + 5
Which is the recursive rule!
Answer:
x + (4x-85) = 90
Step-by-step explanation:
The two angles are complementary which means they add to 90 degrees
x + (4x-85) = 90
Answer: A
Step-by-step explanation:
Both angles are makes a right angle which adds up to 90 degrees so they both have to add up to 90 degrees.