Statistics and Probability Answers

null hypothesis that dancing does not cause rain. If the probability of it raining on a given day is 25% (irrespective of any dancing), how many successive days of rain would be needed to be able to reject the null hypothesis at a 0.01 level of significance, and thus convince that it is wrong?
how many successive days of rain would be need at a 0.05 sig level to be able to reject the null hypothesis?

A sample of n=5 scores has a mean x-bar=8.If a new score X=2 is added to the sample.What value would be obtained for the new sample?

A survey of 100 people revealed that 45 read the wall street journal and 55 read Sports Illustrated and 12 read both. Find the probability that the person does not read Sports Illustrated

There are 23 bulbs in a box and 10 of them are red. The lamplighter takes 2 bulbs at random. What is the probability that chosen bulbs are red?

Life insurance companies must carefully monitor death rates. Before using a life insurance policy for a 19 year old, the company needs to know the death rate for that group. Find the death rate for per 10,000 people during their 19th year. What is the death rate for the 10,000 people for their 19th year?

1.In a raffle, there are 6 different types of prized: 20 $50 gift cards, 5 luxury gift baskets, 5 bottles of Don Perigon Champagne, 2 trips to Vegas, and 1 car and each prize is awarded individually. So far, there have been 9878 tickets purchased, at $5 per ticket, and you are the last person in line.

a.) How many tickets do you need to buy in order to have a 1% chance of winning any prize?

b.) if you buy 20 tickets, what is the probability that you will win a trip to Vegas or a car (or both)?

A random variable X has the following distribution:
Value (x) -3 -2 0 1 2
Prob. p(x) 2/9 1/9 p 2/9 p2
Find p and P(|X+1|>1).

During January the probability that Angela's car fails to start in the morning is 0.2 and this is unaffected by whether or not it started the previous day. When it fails to start, she walks to work. (i)What is the probability that Thursday is the first day of the week (starting on Monday) that she has to walk?(ii)What is the probability that she drives to work every day from Monday to Friday?(iii)What is the probability that she drives to work for exactly 3 days in a week?(iv)What is the probability that she has to walk exactly two days in a row in one week?

GIVEN: 5 MATH BOOKS AND 3 SCIENCE BOOKS . IN HOW MANY WAYS CAN WE ARRANGE ALL THE BOOKS IN A SHELF ?

high temperatures in a certain city for the month of August follow a uniform distributuion over the interval 60 degrees to 85 degrees fareheit. what is the probabilty that a randomly selected August day has high temperature that exceeds 65 degrees