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#426 Re: Help Me ! » Compound Interest » 2011-04-12 08:44:07

98 dollars (98.00)
the account has 6% interest which compounds monthly, how much money would i have after 1 yr.? 10 yrs? after 20 yrs? after 30 yrs?

#427 Re: Help Me ! » Compound Interest » 2011-04-12 08:29:15

i do not mean to but it is that way

#428 Re: Help Me ! » Compound Interest » 2011-04-12 08:13:30

if i do this on my calculator it does not come out like that site. i have  $98.00 (sorry i added the first wrong)

98 x 12 =1176 total money to start with the first year.
98x 6(%) x 12 (months)=7056. Is that the total savings with 6%?

then 98 x that amount for 10/20/30 years?

#430 Help Me ! » Compound Interest » 2011-04-12 05:52:39

survival
Replies: 45

Hello,
If I save $85.00 in a savings account with 6% interest which compounds monthly, how much money will I have after 1 yr/ 10 yrs./ 20 yrs. and 30 yrs. This is by a formula of A = P (1 + r/m) n. I did not know how to get that n up to the top of the last part of the formula.)
Thank you!

#431 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-11 13:27:32

hello bobbym,
I asked and was given these figures:
x= the box of cereal
z = x - x with level over it
z= 453 -451 divided by 10.2
1960, 784, 314
z=-20
.5-.079 then the answer is .421

#432 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-10 15:23:27

I guess I am in for a rough quiz if they are like that. "No more than" is confusing, it could mean anything.

#433 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-10 11:23:03

hello,
Yes, they teach to round sometimes and sometimes don't mention it. Most confusing!

A box of cereal contains 451 g with a standard deviation of 10.2 g. Find the probability that a box contains no more than 453 g. Assume a normal distribution. Use a z-score rounded to 2 decimal places.

z = x - mean
_____________
standard deviation

They did not show the numbers except after it was already divided.
"The area between z = 0 and z = 0.2 is 0.079.
The area to the right of z is 0.421. (Round to nearest thousandth)
Therefore the probability that a box of cereal contains more than 453 g. is approximately 0.421."
I still don't know why all three of us came up with a different answer, although the only answer they wanted was mechanical-theirs.
Look at the answer. Why couldn't the answer have been 0.079? What caused the difference in that and the final answer? I have no clue. Where did the difference in the two numbers come from?

#434 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-10 00:31:59

Sorry, i posted in wrong place. The answer is:
0.421.
What is confusing me is that when you divide the mean by standard deviation, it usually gives you the right answer. This one did not. There was a difference. I worked it the right way and so did you and I cannot explain the difference in answers. I will be back later and post the way the answer is shown.

#435 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-09 17:37:11

Math is interesting after all, if i could just understand it.

#436 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-09 17:35:35

Well, it let me keep it open for one more try. You know how the chart on the positive side has spaces between with no answer on some lines? In my text, it has a chart with numbers that skip like that.
If I know what lies between there, I bet the answer is there. It has me fascinated. I solved another one kind of like it and only got the answer correct, because I'd seen one done in class. It's that space between the z and the A that holds the key.

#437 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-09 15:37:35

ok, i will try that one. It is homework, not a test, but it does tell me the answer when i get it wrong after a couple of tries.

#438 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-09 14:45:37

I typed in the .575 and it didn't take it. I have one more try.

#439 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-09 13:56:16

okay, i am going to type it in and see what happens.

#440 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-09 12:41:10

1 - .4247 = .5753. Isn't that too much?

#441 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-09 12:15:56

I am back, so back to thinking about that problem.

#442 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-09 10:49:32

I need to eat soon.
I am looking at one I worked last night or today and the only difference were the two numbers of grams.

A box of cereal contains 453 g with a standard deviation of 10.2 g. Find the probability that the box contains more than 461 g. Assume a normal deviation. Find the z-score for 461.
The final answer to that one is .0218.

Be back in a bit.

#443 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-09 10:30:30

the answer has something to do with under the curve-to the right or left. I have never spent so much time on one problem.

#444 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-09 09:44:04

no, i am just going by others i have worked and they all have.0 something after the answer. maybe multiply this my 100?

#447 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-09 09:08:05

good thing i don't work n a hospital. Patient would not fare well.

#448 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-09 09:05:27

.196 under z=.475
that is coming from a chart that says Areas Under the Standard Normal Curve.

#449 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-09 08:47:57

.525 Is that the answer?
1 - .475 =.525

#450 Re: Help Me ! » Normal Distribution Using z-scores » 2011-04-09 08:38:47

It shows .196 to be .475. Does that seem right?

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