Mathematics: Post your doubts here!

[syed1995]

One more:-
If the price of rice is raised by 100/3 % then by what percentage must a person reduce his consumption of rice so as not to increase his expenditure!
I understood it but how should I start with it.....can anyone plz tell me how to check and wat statement should i look first which is catch and then how to solve it?

umm this is quite different then the type of questions which I have attempted so no idea. I would say it's inverse proportion + percentage ..

What's the answer? I might be able to help then..

 

[syed1995]

This one!AM is aritmetic mean and gm is geometric mean anyone?

AM and GM isn't in our syllabus so haven't studied that. We have AP and GP but not their mean.

 

[syed1995]

One more:-
If the price of rice is raised by 100/3 % then by what percentage must a person reduce his consumption of rice so as not to increase his expenditure!
I understood it but how should I start with it.....can anyone plz tell me how to check and wat statement should i look first which is catch and then how to solve it?

25%?

 

[parthrocks]

umm this is quite different then the type of questions which I have attempted so no idea. I would say it's inverse proportion + percentage ..

What's the answer? I might be able to help then..

i dont have the answer....can u try???and wat abt last one?

 

[parthrocks]

25%?

can be possible how did u get that but?

 

[parthrocks]

25%?

I am getting 75%

 

[parthrocks]

I am getting 75%

Oops my bad!
yes i also got 25%.
75% is the quantity of rice....so 100%-75%=25% which is it will be reduce by,,,,..

 

[syed1995]

can be possible how did u get that but?

y:x
4y/3:a

since it's inversely propotional we invert it..

y:a
4y/3:x

4y/3*a = y*x
a=(y*x) / (4y/3)
a=3*y*x/(4y)
a=3/4x

Decrease in x = 1-3/4
Decrease = .25
Decrease %= .25/1*100 = 25%

so answer is 25%

 

[Fatima18]

Its extending differntiation of more but common basic of differentitaion will help you out!

Thanx for the reply

 

[syed1995]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s10_qp_11.pdf
Hello!Number 6 guys?

i) Integrate the dy/dx equation to get the equation..

the equation will be in the form .. y = _x^1.5 . . . . + c

now substitute the co-ordinate values for y and x and you should get c.. the equation will be done.

ii) equate dy/dx to 0 to get the stationary values of x ..

then find d2y/dx2 to check the minimum/maximum..

If you don't know any of the above.. I would suggest you consult your teacher or a book .. since this is basic differentiation.

 

[GorgeousEyes]

the particles p and q has a initial speed of 12 and 7 and the final velocity would be zero as they are telling Each particle comes to
rest on returning to the ground.so u know v=0,u =12 and a=g.now get the time for p and same as q.now put the set values like t>0.7 or <1.2

2nd 1 the particles are at the same height.so u need to find the time at first for the same height.apply the formula s=ut+.5at^2 that means 3(ut+.5t^2)=8(ut+.5t^2)

now u get time 0.8s.so now apply the formula v=u-gt and u will get the velocity of the two particles

Thank a milliooon

 

[GorgeousEyes]

Please anyone could explain to me mechanics /jun11 variant 43 no.4 and no.5 urgently ?

 

[Fatima18]

i) Integrate the dy/dx equation to get the equation..

the equation will be in the form .. y = _x^1.5 . . . . + c

now substitute the co-ordinate values for y and x and you should get c.. the equation will be done.

ii) equate dy/dx to 0 to get the stationary values of x ..

then find d2y/dx2 to check the minimum/maximum..

If you don't know any of the above.. I would suggest you consult your teacher or a book .. since this is basic differentiation.

Thanx..well we have covered differentiation bt we still havent reached the part of extending differentitation...so I dont know whether number 6 and 7 of dis paper has to do wid dat part or nt.

 

[Alice123]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s10_qp_31.pdf
7 (ii) n (iii)
please help

 

[Tkp]

Please anyone could explain to me mechanics /jun11 variant 43 no.4 and no.5 urgently ?

ok just see the diagram carefully.the object is in equilbrium.so the frictional force must be opposite to 6.1 N.
so to find the frictional force 6.1+5costheta(as the theta is in the x axis)=f,so f is 7.5
u=f/r(r is mg as the object is in equilbrium)
3rd 1 is same as 1st 1.now the 6.1 is replaced with 8.6n.so 8.6+5c0stheta-f=ma
and the accleration must be in left direction as the object is moving

 

[Tkp]

cnt help with no.4.i also need help in this part

Please anyone could explain to me mechanics /jun11 variant 43 no.4 and no.5 urgently ?

 

[GorgeousEyes]

ok just see the diagram carefully.the object is in equilbrium.so the frictional force must be opposite to 6.1 N.
so to find the frictional force 6.1+5costheta(as the theta is in the x axis)=f,so f is 7.5
u=f/r(r is mg as the object is in equilbrium)
3rd 1 is same as 1st 1.now the 6.1 is replaced with 8.6n.so 8.6+5c0stheta-f=ma
and the accleration must be in left direction as the object is moving

Thaaanks !

 

[GorgeousEyes]

cnt help with no.4.i also need help in this part

So we will have to w8 for someone to explain this to us

 

[Tkp]

So we will have to w8 for someone to explain this to us

haha.ur right

 

[Rahma Abdelrahman]

Ya rahmaaa thank youu .. hahaha bas msa shr7ty 7elw

bgadd? shokran