If x varies directly as 2n+1, and n=4 when x=6, find n when x=18

irst, find the z score of a score of 80. this is given by the formula z = (x-u)/o, where x is the score, u is the mean, and o is the standard deviation. this gives

z = (80-78)/12 = 1/6 = .1667

now, find what percentile a z score of 1/6 correlates to in the normal distribution.

a z score of 1/6 = .1667 is equivalent to the 56.36th percentile of the distribution. so the probability a score is over this is 1-.5636 = .4364

the mean of a sample mean is equal to the original mean. however, the standard deviation of a sample mean is equal to the original standard deviation divided by the square root of n (sample size). so the new standard deviation is 12/sqrt(16) = 3.

the new z score is 80-78/3 = 2/3 = .667. this is equivalent to the 74.86th percentile. so the probability that the mean will be greater than this score is 1-.7486 = .2514.

answer:

some responsibilities that come with having a checking account -

1. we have to maintain check register with exactness to avoid checks being returned for insufficient funds which is called bouncing a check.

2. we need to update our check register each time we make a transaction using a convenience card. updating check register will   save   us from   overdrawing of checking account.

3. read the agreement the bank gave you when you signed up for our checking account. this includes all the fees and the minimum balance we need to keep in our account to avoid maintenance charges.  

explanation:

note : -   checking account is a transactional deposit account. we can use it to deposit and withdraw funds. money in a checking account is very liquid. it   can be withdrawn using electronic debits, automated cash machines, or checks among other methods.