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2 years ago

The variance Var(x) for the binomial distribution is given by equation :

Mathematics

1 answer:

aliina [53]2 years ago

6 0

Answer: d. np(1 - p).

Step-by-step explanation:

Let x be any binomial variable which represents the number of success such that $X\sim B(n, p)$ , where n is the sample size or the total number of trials and p is the probability of getting success in each trial .

Then, the mean E(x) and the variance Var(x) for the binomial distribution is given by equation :

$E(x)=\mu=np$

$Var (x)=\sigma^2=np(1-p)$

where n is the sample size or the total number of trials and p is the probability of getting success in each trial .

Therefore , the correct option is option d. np(1 - p) .

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If a person tosses a coin 23 times, how many ways can he get 11 heads

EastWind [94]

Tossing a coin is a binomial experiment.

Now lets say there are 'n' repeated trials to get heads. Each of the trials can result in either a head or a tail.

All of these trials are independent since the result of one trial does not affect the result of the next trial.

Now, for 'n' repeated trials the total number of successes is given by

$_{r}^{n}\textrm{C}$

where 'r' denotes the number of successful results.

In our case $n=23$ and $r=11$ ,

Substituting the values we get,

$_{11}^{23}\textrm{C}=\frac{23!}{11!\times 12!}$

$\frac{23!}{11!\times 12!}=1352078$

Therefore, there are 1352078 ways to get heads if a person tosses a coin 23 times.

3 0

2 years ago

Jadyn is looking to purchase a home for $182,000 and will make a $40,000 down payment in order to borrow the remainder. Jadyn’s

AysviL [449]

Answer: Jadyn’s monthly mortgage payment is $812

Step-by-step explanation:

The cost of the house is $182,000.

The down payment made is $$40,000. The balance to be paid would be

182000 - 40000 = $142000

We would apply the periodic interest rate formula which is expressed as

P = a/[{(1+r)^n]-1}/{r(1+r)^n}]

Where

P represents the monthly payments.

a represents the amount of the loan

r represents the annual rate.

n represents number of monthly payments. Therefore

a = $142000

r = 0.00351/12 = 0.000293

n = 12 × 15 = 180

Therefore,

P = 142000/[{(1+0.000293)^180]-1}/{0.000293(1+0.000293)^180}]

142000/[{(1.000293)^180]-1}/{0.000293(1.000293)^180}]

P = 142000/{1.054 -1}/[0.000293(1.054)]

P = 142000/(0.054/0.0003088)

P = 142000/174.87

P = $812

6 0

2 years ago

Half of a class took Form A of a test, and half took Form B. Of the students who took form B, 39% passed. What is the probabilit

mr Goodwill [35]

Answer:

NOT VERY LIKELY

Step-by-step explanation:

• 1/2 OF THE CLASS TOOK FORM A

• 1/2 = 50%

• THE CHANCE CANNOT BE OVER 50%

• 39% OUT OF 50% PASSED

• 50% - 39% = 11%

• THE ANSWER IS NOT VERY LIKELY

5 0

2 years ago

Roberto listed his assets and liabilities on a personal balance sheet.

mixer [17]

To see the effect on Robertos balance sheet, we will first have to get the total assets and liabilities
Total assets = cash+ investment+ house + car
Total liabilities= credit card + personal loan + mortgage + car loan
Substituting the values, we will get
Total asset =$166000
Total liabilities =$1010000
Difference= $844000
To pay off car loan, he uses his investment
Total asset = $166000-5000
=$161000
Total liabilities= $1010000-5000
=$1005000
Difference=$844000
Therefore the answer is letter C, the difference between asset and liability will remain the same.

7 0

2 years ago

Read 2 more answers

3.5 hours:$10 1/2 hour:$1.25. What is the unit rate in dollars per hour for each company?

Rasek [7]

One company wants $10 per 3.5 hours, so they want 10 / 3.5 ≈ 2,86 dollars per hour (after rounding to the closest hundreths).

Second company wants $1.25 per half an hour, so they want 2 * 1,25 = 2,50 dollars per hour.

The unit rate is 2,86:2,50

7 0

2 years ago