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Ask here if you need any help with the General Maths questions/ topics! :D (1 Viewer)
- Thread starter mrh94
- Start date
i got a mean of 54 as well. The way i did it was:
you know that 5 scores = 62.
say the first score is x then the second is x+1, the third x+2 etc.
therefore you get this equation: x+(x+1)+(x+2)+(x+3)+(x+4)/5 = 62 i.e. i just added up all the scores and divided by 5.
this simplifies to 5x+10/5 = 62
x+2=62
x=60
now your going to add one more score which is 14:
x+(x+1)+(x+2)+(x+3)+(x+4)+14/6 = the new mean (call it y)
now just sub in x=60 for x in the above equation, do some algebra by solving for y and you get the new mean of 54
you know that 5 scores = 62.
say the first score is x then the second is x+1, the third x+2 etc.
therefore you get this equation: x+(x+1)+(x+2)+(x+3)+(x+4)/5 = 62 i.e. i just added up all the scores and divided by 5.
this simplifies to 5x+10/5 = 62
x+2=62
x=60
now your going to add one more score which is 14:
x+(x+1)+(x+2)+(x+3)+(x+4)+14/6 = the new mean (call it y)
now just sub in x=60 for x in the above equation, do some algebra by solving for y and you get the new mean of 54
wavess
Member
Ohhhh I see, now I get the whole method! Thank you!! I would always skip this question when I came across it. Thanks
a quick overview of annuities:
whenever you see work out interest you use I=PRT.
If you see compound interest use: A=P(1+r)^n. Also be careful with compound interest and note whether its compounded annually, 6 monthly (half yearly) quarterly etc. with these you have to make your adjustments to the rate and time. e.g. half yearly you have to divide the rate by 2 and multiply the time by 2... so 6%pa compounded half yearly for 2 years would mean r=3% (6/2 = 3) and n=4 (i.e. there are four half years in 2 years).
If asked for flat rate in loan repayments: use I=PRT
If asked for reducible interest in loan repayments: find what the interest is, add this to the original principal and then subtract whatever you are paying off say $1000 per year. this will be your new principle to use in year 2. Repeat this process for however many years you need BUT make sure you always use the new principal
I hope this helps
whenever you see work out interest you use I=PRT.
If you see compound interest use: A=P(1+r)^n. Also be careful with compound interest and note whether its compounded annually, 6 monthly (half yearly) quarterly etc. with these you have to make your adjustments to the rate and time. e.g. half yearly you have to divide the rate by 2 and multiply the time by 2... so 6%pa compounded half yearly for 2 years would mean r=3% (6/2 = 3) and n=4 (i.e. there are four half years in 2 years).
If asked for flat rate in loan repayments: use I=PRT
If asked for reducible interest in loan repayments: find what the interest is, add this to the original principal and then subtract whatever you are paying off say $1000 per year. this will be your new principle to use in year 2. Repeat this process for however many years you need BUT make sure you always use the new principal
I hope this helps
Last edited:
wavess- I copied my answer from the other location where you posted this:
Ok.. I will explain what I did:
The longitude difference between Osaka (135degreesE) and Denver (105degreesW) is (135degrees +105degrees) =240degrees.
Since 1degree longitude difference
= 4 min of time difference
240degree longitude difference
=(4*240)min
=960min
=16hr
Since Denver is to the West of Osaka, the local time in Denver is 16hr behind of the local time in Osaka.
Sent Denver time:
=(10:00am-16h)Thurs
=6.00pm Wednesday
Received:
=6.00pm +14hrs
=8am Thursday.
PS How to post a new thread> Click post new thread button. Add details and once done click the submit new thread button. (Easy, nothing to it really!)
wavess
Member
Thank you for your help, I was going 6am - 14 hrs instead that's why I kept getting it wrong.
And I can't see the post new thread button. I tried looking!
Ahh bugger.. that would do it!
*It is a blue button top left hand corner whenever you are inside of a particular forum area.