On line Study Group (1 Viewer)

[Dr_Doom]

Hey has anyone seen question 20 in the 2001 paper? How on earth do you do this.

Here I have the answer:

In ABC:

tan 25 = 100/AC
AC = 100/tan25
=214.4506....m

In DBC:

tan 76 = 100/DC
DC = 100/tan76
=24.9328...m

AD = AC - DC
= 214.3406... - 24.9328...
189.5178...
=190m.


OR


In DBC:

sin 76 = 100/DB
DB = 100/sin76
= 103.0613...m

In ABD:

<ADB = 180 - 76
= 104
<ABD = 180 - 25 - 104
=52

Using the sine rule:

AD/sin 51 = DB/sin25
AD = DBsin51/sin25
=103.0613...sin51/sin25
189.5178...
=190m

 

[emanuellasker]

Thanks for the help, no I know it was one like yesterday but I didn't know how to get sin 51, I haven't done angle sum of a straight line = 180 as long as there is the arm their for years, I spent two hours on it before finding the naswer on the internet. Thanks for the help, none the less and best of luck tommorrow.
Cheers,
Fellow HSC student.

 

[BartmanX]

OK, well...
Q:
Mean is 6.25%
Standard Deviation is 0.25 % Harlan gets a reading of 5.75% What is Harlan's reading as a z- score?

Z Score = - 2

 

[cooldudehack]

3 years later rofl

 

[Vueyt]

Q. The local ranger decides to investigate this using the capture-recapture method. She captures 5 of these mammules one night, tags them and releases them. The following night she returns and captures another 10 and notices that 2 of these are tagges. Find a reasonable estimate for the total number of these mammules.

Thanks in advance

----------------------

 

[orly?]

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there's an easier way to do it but whatever floats ur boat

 

[crazathiest]

Has anyone got year 12 General maths notes/detailed help on the topics studied in year 12 maths?

Thanks.

 

[davidbarnes]

Has anyone got year 12 General maths notes/detailed help on the topics studied in year 12 maths?

Thanks.

The BOS user posted notes are a good starting point.
http://www.boredofstudies.org/view.php?course=4

 

[Seza16]

The teachers at our school give us photocopies of the Excel Study guide and there is another study guide they use as well.

The way i study for general maths is having the formulas written out on a piece of paper with an example of how to use the formula and laminated and use it as a place mat. I also have them on my wardrobe doors so im always looking at them.

 

[tashie babie]

I am very interested bout forming an online sdy group
Tash

 

[aggi]

Is anyone interested in forming an on line study group to help each other out with this subject? As you know, the HSC is looming, and I thought we could all help each other out.

Yes i would love to participate in an online study group!!=]

 

[acinad//]

PLEASE HELP ME. heres a question/subject i dont understand.

mike plays a game in which he has:

• 1/10 chances of winning $20
• 1/2 chances of winning $1
• 2/5 chances of losing $2

what is his financial expectation when playing this game?

• $1.70
• $3.30
• $17
• $19

 

[bling05]

Financial Expectation = (1/10 x $20) + (1/2 x $1) - (2/5 x $2)
= $1.70

 

[acinad//]

thanks heaps ^_^

 

[calcie]

helppp

help pleaseeee. i have no idea how to do this question.

 

[crystal.s]

hey calcie.

now im not 100% sure if this is how you work your question out. BUT the angle of elevation is equal in size to the angle of depression, as alternate angles are equal.

so angle M=75* .

to find out the elevation i THINK you just divide that 75* by 2. so angle of elevation=38*

but i dont get why they have the measurements JK and MK. maybe its to try and confuse us. or i just dont get it either and im completely wrong lol

do you know what the answer is?

 

[calcie]

the answers say 58*

lucky i still have a bit of time before HSC to attempt to learn all of this.

 

[tacogym27101990]

the answers say 58*

lucky i still have a bit of time before HSC to attempt to learn all of this.

if you still need help with it:
angleMJK = 15*
so using the sine rule: sin15/mk = sinJMK/JK
sin15/18=sinJMK/20
sinJMK= 20sin15/18
so JMK = 16*43'
therefore KML = 75* - 16*43'
=58* (nearest degree)

 

[calcie]

thanks heaps
i new it would of had to be something relatively simpleish

 

[hsc100]

<HR style="COLOR: #d1d1e1" SIZE=1> <!-- google_ad_section_start -->Does anyone know the answers and working out to these general mathematics problems? If so can you plz help

1. A cylindrical wheat silo is 40m high and 20m in diameter

a) If paint covers 8m square per litre, find the number of 10 litre cans of paint needed to paint the silo with one coat?

b) Paint costs $115.20 per 10 litre can.find the cost of the paint for the silo


2.How many spheres of 15cm diameter can be covered by 10m square of material


3.Determine the total area of leather in 20 dozen cricket balls each with diameter 7cm