Answer:
It would take Beth twelve minutes to wash the car herself
Step-by-step explanation:
If they do it together in 6 minutes.
& Katy can do it in 18 minutes alone
Then 18 - x = 6
replace x for twelve
18 - twelve = 6
Ans: twelve
Answer:
x = 4
Step-by-step explanation:
we know that 72 and (2x + 10) add up to 90
90-72 = 18
(2x + 10) = 18
2x = 8
x = 4
Answer: 1) 0.6561 2) 0.0037
Step-by-step explanation:
We use Binomial distribution here , where the probability of getting x success in n trials is given by :-

, where p =Probability of getting success in each trial.
As per given , we have
The probability that any satellite dish owners subscribe to at least one premium movie channel. : p=0.10
Sample size : n= 4
Let x denotes the number of dish owners in the sample subscribes to at least one premium movie channel.
1) The probability that none of the dish owners in the sample subscribes to at least one premium movie channel = 

∴ The probability that none of the dish owners in the sample subscribes to at least one premium movie channel is 0.6561.
2) The probability that more than two dish owners in the sample subscribe to at least one premium movie channel.
= ![P(X>2)=1-P(X\leq2)\\\\=1-[P(X=0)+P(X=1)+P(X=2)]\\\\= 1-[0.6561+^4C_1(0.10)^1(0.90)^{3}+^4C_2(0.10)^2(0.90)^{2}]\\\\=1-[0.6561+(4)(0.0729)+\dfrac{4!}{2!2!}(0.0081)]\\\\=1-[0.6561+0.2916+0.0486]\\\\=1-0.9963=0.0037](https://tex.z-dn.net/?f=P%28X%3E2%29%3D1-P%28X%5Cleq2%29%5C%5C%5C%5C%3D1-%5BP%28X%3D0%29%2BP%28X%3D1%29%2BP%28X%3D2%29%5D%5C%5C%5C%5C%3D%201-%5B0.6561%2B%5E4C_1%280.10%29%5E1%280.90%29%5E%7B3%7D%2B%5E4C_2%280.10%29%5E2%280.90%29%5E%7B2%7D%5D%5C%5C%5C%5C%3D1-%5B0.6561%2B%284%29%280.0729%29%2B%5Cdfrac%7B4%21%7D%7B2%212%21%7D%280.0081%29%5D%5C%5C%5C%5C%3D1-%5B0.6561%2B0.2916%2B0.0486%5D%5C%5C%5C%5C%3D1-0.9963%3D0.0037)
∴ The probability that more than two dish owners in the sample subscribe to at least one premium movie channel is 0.0037.