MedVision ad

2012 Year 9 &10 Mathematics Marathon (5 Viewers)

ymcaec

Member
Joined
Apr 25, 2012
Messages
77
Gender
Undisclosed
HSC
N/A
Re: 2012 Year 9 &10 Mathematics Marathon

heres one for ya, show that the some of the numbers 1+2+3...+99+100 = 5050

learnt that long time ago
(i hv seen this question in a yr 7 paper btw)
 

Demento1

Philosopher.
Joined
Dec 23, 2011
Messages
866
Location
Sydney
Gender
Male
HSC
2014
Re: 2012 Year 9 &10 Mathematics Marathon

For the benefit of more year 9 and 10 students here's a more moderate one for you guys:

An empty diving pool is in the shape of a rectangular prism, 6 metres long and 4 metres wide. Water is flowing into the pool at a rate of 800 litres per hour. What is the depth of the water after 5 hours?

NB: ymcaec, this would be too easy for you. Let some other people have a go.
 

kev-

Member
Joined
Feb 11, 2012
Messages
84
Gender
Male
HSC
2014
Re: 2012 Year 9 &10 Mathematics Marathon

An empty diving pool is in the shape of a rectangular prism, 6 metres long and 4 metres wide. Water is flowing into the pool at a rate of 800 litres per hour. What is the depth of the water after 5 hours?
Water after 5 hours
=800x5
=4000L

let a be height/depth
Volume of diving pool
=6x4xa
=24a m^3
=24000a L

equate: 24000a = 4000
a= 1/6 m
 

Triage

Member
Joined
May 30, 2012
Messages
245
Gender
Undisclosed
HSC
N/A
Re: 2012 Year 9 &10 Mathematics Marathon

sinx-cosx=0 solve?
 

SpiralFlex

Well-Known Member
Joined
Dec 18, 2010
Messages
6,960
Gender
Female
HSC
N/A
Re: 2012 Year 9 &10 Mathematics Marathon

Who here would like to do a Spiral exam?
 

kazemagic

Member
Joined
Feb 8, 2012
Messages
626
Gender
Male
HSC
2014
Re: 2012 Year 9 &10 Mathematics Marathon

Here's another one:
Peter stands due south of a pole. Sam stands 10m due east of Peter. The angle of elevations of Peter and Sam to the top of the pole is 25(degrees) and 15(degrees) respectively. Find the height of the Pole.
 

kev-kun

Member
Joined
Mar 24, 2011
Messages
157
Location
Sydney, Australia
Gender
Male
HSC
2014
Re: 2012 Year 9 &10 Mathematics Marathon

Here's another one:
Peter stands due south of a pole. Sam stands 10m due east of Peter. The angle of elevations of Peter and Sam to the top of the pole is 25(degrees) and 15(degrees) respectively. Find the height of the Pole.
3.65 metres?
 

Demento1

Philosopher.
Joined
Dec 23, 2011
Messages
866
Location
Sydney
Gender
Male
HSC
2014
Re: 2012 Year 9 &10 Mathematics Marathon

o_O I got 3.27 for that one. How did you do it?
Sorry that I didn't see this Q earlier. After about 3/4 of a page of working, I had 3.27 metres. I treated the length of P to the pole as 7.02 (2 d.p.).
 

kat-

msftsrep
Joined
Apr 3, 2012
Messages
334
Gender
Female
HSC
2014
Re: 2012 Year 9 &10 Mathematics Marathon

I feel like an idiot, can't get my head around this one. drew a 3D diagram and everything
 

Demento1

Philosopher.
Joined
Dec 23, 2011
Messages
866
Location
Sydney
Gender
Male
HSC
2014
Re: 2012 Year 9 &10 Mathematics Marathon

I feel like an idiot, can't get my head around this one. drew a 3D diagram and everything
Nah, don't worry too much about it. Never get thrown off by a question simply because it seems new to you. Make an effort to interpret it. If it doesn't hit you, take a break, have fun and relax and get back to the question once your mind is refreshed. Often, the human mind takes longer to comprehend things at times so it's perfectly normal not to get it the first time around.

When you do problem solving, think this: 'I have all this given information and thus I will record it but what do I need?'
 

Users Who Are Viewing This Thread (Users: 0, Guests: 5)

Top