High School Math Help. PLEASE??????????

Question

At a fast-food restaurant, the time spent by the customers is a normally distributed variable. After randomly recording the habits of 200 custowers, the average amount of time spent was found to be 26 minutes with a standard deviation of 2.8 minutes. What proportion of customers spent more than 30 minutes in the restaurant? If a customer arrives at 11:05 a.m., what is the probability that the customer will leave at 11:30 a.m. or earlier?

Answer 1

26 +2.8 = 28.8 26 - 2.8 = 23.2 1 1 standard Deviation from the mean.
2.8 x 2 = 5.6 and has the range between
20.4 to 31.6 2 standard deviations form the mean.
30 minutes is almost 2 standard deviations from the mean; approximately 95 percent for a normal distribution. So there is about a 5% of the customers will spend 30 minutes or more.
A customer arriving at 11:05 and leaving at 11:30 spends 25 min which has a 68% chance or probability. This part is encompassing approximately 68% of the population.

Answer 2

the abilities required to be a caveman residing in a hundred,000 BC Europe have been quite complicated and time-eating and required very a good number of potential and ingenuity. yet no person has those skills any further. Fifty years in the past, it grow to be a useful potential to be waiting to characteristic and subtract long lists of numbers manually and precisely. you'll be paid a solid salary to accomplish that. no longer any further. utilising a calculator wisely is an substantial potential now, and can be purely as complicated a job as long branch. this is extra substantial at present to be waiting to *estimate* the consequence of a calculation than to do it by using hand precisely astounding, so as which you would be able to verify the calculator. (yet unfortunately they can't do this the two). the main suitable use of a calculator or Mathematica may well be purely peachy by using me. however the topic is they are able to't even use a calculator wisely, purely as you're saying!! Arghe! there are a number of the thank you to income perception into arithmetic, and studying algorithms for addition multiplication and integration is purely one way. there is not any reason to suspect that drawing near arithmetic in a distinctive way might inevitably bring about much less expertise or appreciation of the topic. In different words, there's a form skills in arithmatic, which contain estimation and translating statements from English (or in spite of vernacular) into formalism (extra substantial in 2010) and handbook algorithms (extra substantial in 1950) as properly as form concept, set concept, etc. i think of the foremost situation is that extra pupils desire college ranges now just to get jobs, and human beings that have not have been given the abilities to be in college are in spite of the undeniable fact that enrolling.