Maths Questions

Rexina182 · Apr 13, 2009

1)

I have calculated that, when taking the car for an MOT, the probability the brakes fail is 1/10, the headlights fail is 1/4 and the wipers fail is 1/5. But what's the probability only one of the parts fails?

2)

Point P lies on the curve y = x2 - 6x - 16 where m = 0. What are the co-ordinates of p?

Ajr · Apr 13, 2009

1)55%
2)That doesn't make sense to me without a diagram?!

Rexina182 · Apr 13, 2009

1) (1/4 x 9/10 x 4/5) + (3/4 x 1/10 x 4/5) + (3/4 x 9/10 x 1/5) = 0.375 (or 75/200)

2) Any +/- x^2 curve is symmetrical and where m = 0 is the mid point of the curve. Therefore:

Factorise to give (x+2)(x-8) where x = -2 and +8. The difference between the two x points is 10 therefore halfway is 5.

-2 + 5 = 3 or 8 - 5 = 3 therefore x = 3 where m = 0

y = x2 - 6x - 16 therefore 9 - 18 - 16 = -25

Co-ordinates of p are (3,-25).

No need for a digram.

BenG · Apr 13, 2009

Its easter holidays and college is closed. I dont have to study maths for another week, give me a break !

Why are you asking the question if you know the answer? was it just a test or are you trying to look clever ?

Rexina182 · Apr 13, 2009

Just a test. I sit here bored and just thought I throw them into the mix. I used to do the same over on Renaultsport until was banned for suggesting a link between children and Catholic priests.

Ajr · Apr 13, 2009

I did A level maths, and i can't remember a single bit of it? Shocking!

Berty · Apr 13, 2009

Ajr said:
I did A level maths, and i can't remember a single bit of it? Shocking!

I was thinking something very similar, I did engineering in uni so plenty of maths there, and now can't even do GCSE level maths. That means the older I get the dumber I get.

BenG · Apr 13, 2009

I did A level maths, and i can't remember a single bit of it? Shocking!

Im studying for HNC in Electrical and Electronic Engineering, There is loads of maths as you can imagen. I find the HNC maths pretty easy tbh, I just learn what I need to know for the exams and pretty much forget everything after that as I dont use it in the real world.

Its all a load of b***ocks !

Ajr · Apr 13, 2009

Did level 3 C&G Electrical and electronic engineering & servicing, forgotten most of that too, despite getting pretty much straight distinctions. Same with languages, straight As & A*s, forgotten most.

I think unless you use the knowledge daily it's likely you'll forget it pretty soon. It's the understanding of how it all works that you never forget, the methodology. So it would be very easy to bring the memories back with some quick revision.

artdealer · Apr 13, 2009

I think the wipers and brakes are more like 100% on a Trophy and the dampers will pass even though they are like a soggy Expression 1.2. Factor that little lot in and what comes out..

BenG · Apr 13, 2009

I have my C&G NVQ level 3 in electrical engineering too. Whats your job ? (if you dont mind me asking)

hoolio · Apr 13, 2009

I think I'll just go and sit in the corner with my dunces hat on.

Berty · Apr 14, 2009

hoolio said:
I think I'll just go and sit in the corner with my dunces hat on.

Can I join you. I may have the degree certificate but I feel a bit of a fraud, all I can remember from uni is how good picadilly 21's in manchester was on a wednesday night.

quik5i1ver · Apr 14, 2009

If anyone feels like providing a random question of any subject matter on a daily basis, I think it would be quite interesting....

Beef-Mc · Apr 14, 2009

It's weird thinking I used to be able to that all that in minutes, but now it just makes me go #-o

reboot · Apr 15, 2009

quik5i1ver said:
If anyone feels like providing a random question of any subject matter on a daily basis, I think it would be quite interesting....

quik51lver, I completely agree with you, but I have a feeling Rex needs no encouragement at all.....

less maths though, please. I am rubbish at it, apparently like a few others here...

quik5i1ver · Apr 15, 2009

As per some previous comments, my degree was fairly maths/science based and I battled through maths A-Level so I would like to have a chance to remind myself of my long lost mathematical skills... Plus languages etc.

As I suggested originally - a random daily subject, not always maths!

hoolio · Apr 15, 2009

quik5i1ver said:
As per some previous comments, my degree was fairly maths/science based and I battled through maths A-Level so I would like to have a chance to remind myself of my long lost mathematical skills... Plus languages etc.

As I suggested originally - a random daily subject, not always maths!

Er yeah, we're all waiting....................

BenG · Apr 15, 2009

An open cylinder has to contain 2500cc of liquid when full. Calculate the radius and height in cm so that the least surface area of metal is used.

Jonc · Apr 15, 2009

Rexina182 said:
1)

I have calculated that, when taking the car for an MOT, the probability the brakes fail is 1/10, the headlights fail is 1/4 and the wipers fail is 1/5. But what's the probability only one of the parts fails?

The probability of getting this answer right is slim since you have to factor in an element of randomness that's inherent in all French made cars! Plus it's a trick question since its never just one part that fails!!!