Problem Solving

Hi, actually I have 2 more tests and they seem very very hard, sorry for my sickness. Because I really don't know how to solve them , but if you help me again i will be very thankfull for it!
If you can solve at least one of them , please save my life!
There are questions:

1.
On average at a certain road junction there are 3 accidents per month. An accident may include any number of vehicles and is an independent event, so a vehicle that skids on oil discharged onto the road from an earlier accident is still attributed to that accident.
if we take a month as defined as exactly 30 days, what is the probability of there being 2 or more accidents on any day?
answers :
It is not possible to answer this question
0.0047
0.8008
0.0
4.95025E-05

2.
An oil terminal can handle 10 tankers on any day and on average receives 7 per day. What are the expected number of days in a 365 day year that there will be too many tankers arriving for the terminal to deal with?
answers:
0.012
32
36
19
0.071

3.
On average a machine breaks down 1.5 times in any year what is the standard deviation of the number of breakdowns in a year?

no answers:(

Please, with solutions

pleaaase!

navai wrote:pleaaase!

I don't know about others, but I tend to ignore threads that contain multiple questions or that contain questions that are clearly not related to the GMAT.

For example, the 5th answer to your first question is "4.95025E-05" - while that might be something that shows up on a calculator that's run out of space to display the answer, that's something that you would NEVER see on the GMAT. The other answer choices (randomly arranged, very strange numbers) also clearly indicate that it's a non-GMAT question.

Your 2nd question is also way beyond the scope of the test.

Your 3rd question is both unanswerable and outside the scope of the GMAT.

Stuart Kovinsky wrote:

navai wrote:pleaaase!

I don't know about others, but I tend to ignore threads that contain multiple questions or that contain questions that are clearly not related to the GMAT.

For example, the 5th answer to your first question is "4.95025E-05" - while that might be something that shows up on a calculator that's run out of space to display the answer, that's something that you would NEVER see on the GMAT. The other answer choices (randomly arranged, very strange numbers) also clearly indicate that it's a non-GMAT question.

Your 2nd question is also way beyond the scope of the test.

Your 3rd question is both unanswerable and outside the scope of the GMAT.

thank you for your help, i am proud that there are the experts like you.