probablility, annuities and Sperical Geometry (1 Viewer)

ally147

New Member
Joined
Jun 1, 2005
Messages
22
Location
Batlow
Gender
Female
HSC
2006
At the moment these are the subjects i struggle with the most.

I find that i stress really badly in exams and tell myself that i can't do it, hence stressing so much, hence almost failing.

I don't fail but i know if i had things embedded in my head a bit more then i might be a little happier with my marks and results...I would like to be higher in the ranks of my class.

Anyone that can give some tips on these areas and on how i should study then i will kiss their toes lol...that was a joke but i would be greatly appreciative towards you.

Thank you
 

taki999

Member
Joined
Mar 7, 2006
Messages
195
Location
Sydney
Gender
Male
HSC
2006
someone's got a fetish for feet.
Okay..on track now.
probability:
you must know how to use the percentages by doing the tree graphs. This is simply done by longing at your test book in the graphing section for probability. Apart from that you must remember to read the Q properly, when they say Replacing the marbles for eg. 5 green marbles and 4 red marbles...one is replaced what is the probability. so lets say 1 red marble is taken out and NOT replaced, and the Q asks what is the chance to get another red marble.. 3/8 is the chance to draw another red marble.
For annualties you have to remember the formulas for the Questions then apply it by using the graph for interest and put it in the formula.

Hope that helped a bit.
 

PC

Member
Joined
Aug 19, 2004
Messages
639
Location
Sydney
Gender
Undisclosed
HSC
N/A
Probability, Annuities and Spherical Geometry ... that's a fairly big chunk of stuff!

You might be better off asking about specific questions or sections instead.

PROBABILITY TIPS?
• Always give answers as simplified fractions unless asked otherwise.
• Remember that you always get a value between 0 and 1.
• Always make sure that you have two parts: number of ways your event can occur, divided by the total number of possible outcomes.
• For permutations and combinations, just ask yourself if the order in which you select the items are important. If the order is NOT important, then you divide. (A few examples will help here.)
• Probabilty trees, write the probabilities on the branches and multiply along each branch.

ANNUITIES TIPS?
• Make sure you use a graphic calculator if you can. Seriously.
•*Future value/Present value ... say you want to get a balance of $5000 in 5 years from now. You can do that by saving a certain amount of money into your account every month. You can use the FV rule to work out what that amount needs to be. OR you can invest a large SINGLE lump sum now that will grow to the same amount, $5000, under compound interest. The single lump sum is the PV.
• For loans, ALWAYS use the PV rule, and the amount of the loan is the present value.

SPHERICAL GEOMETRY?
• Make sure you know east from west. North and south seems a bit easier.
•*Know the difference between great circles and small circles.
•*Know the arc length of a circle formula.
• There are heaps of little knowledge bits in this topic...
• 1 nautical mile = 1.852 km
• 1 nautical mile is defined as 1 minute along a great circle, 60 nm = 60 minutes or 60 nm = 1 degree ... so 1 degree along a great circle is 60 nautical miles, so to find a quick distance along a great circle you can do angle x 60 and get the distance in nautical miles.
• In 24 hours, the world turns 360 ... in 1 hour the world turns 15, so the time difference in hours is simply the angle ÷ 15. DON'T try to remember any other way of doing it, it will make things too confusing.
• Remember the Speed/Distance/Time formulas.
• 1 knot = 1 nautical mile per hour ... it's just a unit of speed. Really, when you see knots (and you will) it looks like "knots" but you read it as "nautical miles per hour".

Hope this helps. I owe you for the Sharp calculator info.
 

Dr_Doom

Active Member
Joined
Oct 16, 2005
Messages
1,238
Location
NSW
Gender
Male
HSC
2006
how can u have a fettish for feet. It's not like u can have sex with feet.... :S
 

PC

Member
Joined
Aug 19, 2004
Messages
639
Location
Sydney
Gender
Undisclosed
HSC
N/A
Dr Doom,

Humans have 20 digits - 10 fingers and 10 toes.

Some people are only good with their hands..............
 

ally147

New Member
Joined
Jun 1, 2005
Messages
22
Location
Batlow
Gender
Female
HSC
2006
ok here's a question to be more specific....

Colombo in Sri Lanka has latitude 7*N and longitude 80*E. If a cricket match begins at 11:00am Colombo time, what time will it be in Sydney (134*S, 159*E)? Ignore time zones.

(A) 6:20am
(B) 3:20pm
(C) 3:40pm
(D) 8:24pm

Thanks guys
 

kolgf

Member
Joined
Nov 24, 2005
Messages
37
Location
sydney
Gender
Undisclosed
HSC
2006
159*-80* = 79*

79*/15*(15* = 1 hour)

= 5h 16m

11am + 5h 16m ( because sydney is infront of colombo so we add)

= 4:16pm

E) none of the above :p
 

PC

Member
Joined
Aug 19, 2004
Messages
639
Location
Sydney
Gender
Undisclosed
HSC
N/A
All of what kolgf has said PLUS ... I'd always draw a diagram first.

View attachment 13343

At least it makes it easier to see why Sydney is ahead of Colombo.

By the way, how do clever people manage to get the image to show up in their posts? I've done it once, but it was ages ago.
 
Last edited:

ally147

New Member
Joined
Jun 1, 2005
Messages
22
Location
Batlow
Gender
Female
HSC
2006
I got the same (4:16) but it is none of the answers.... anyone else wanna give it a go??? I need help lol.
 

PC

Member
Joined
Aug 19, 2004
Messages
639
Location
Sydney
Gender
Undisclosed
HSC
N/A
SoulSearcher said:
Upload the image onto a website, then use the [IMG ] URL [ /IMG] tags, without the spaces :)
Too much hassle for me! ... but thanks for the tip.
 

PC

Member
Joined
Aug 19, 2004
Messages
639
Location
Sydney
Gender
Undisclosed
HSC
N/A
ally147 said:
I got the same (4:16) but it is none of the answers.... anyone else wanna give it a go??? I need help lol.
I wouldn't get too worried about it. You seem to be getting the same as me and a few others, so consensus rules. Your answer is fine.
 

kacca29

New Member
Joined
Jan 2, 2004
Messages
18
Gender
Male
HSC
N/A
No, not one of the options but certainly correct.

Perhaps you transcribed the question incorrectly, or the question is just wrong (it does happen:)
 

ally147

New Member
Joined
Jun 1, 2005
Messages
22
Location
Batlow
Gender
Female
HSC
2006
I'll go with the question being wrong lol..... I'll get my teacher to check it... My maths trial is on next Wednesday :'(
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top