IGCSE MATHS Doubts

[Shazizzzle]

what is the rule for compound intrest please no symbols full words

The principal amount is the one you invest.

The formula for compound interest, P(1+r/100)^t, is when, P is principal amount, r, the rate, and t, the time.

If the rate is yearly, then the time, t, must too be in years.
If the rate is monthly, the time, t, must be monthly too.

The answer you get to the formula above IS NOT THE INTEREST. It is the TOTAL AMOUNT.

If you invest 200, and the answer you get to the formula is 300, the 300 is not the interest, rather the TOTAL you get.

The interest is, total - principal, 300 - 200 = 100.

[rahuldevnani93]

Guys I need the markscheme for the old paper 1988 - 1995
Please

Email to :- rahul_gurukul@yahoo.com

[Vin]

2009 may/june

22c
i know the answer is probably staring at me in the face, but please tell me :/

sorry its a bit untidy .. i think its a lot untidy ..

[The Golden Girl =D]

Guys I need the markscheme for the old paper 1988 - 1995
Please

Email to :- rahul_gurukul@yahoo.com

it's in this website jut so u know ..ohh but not the whole thing  

[Baladya]

http://www.freeexampapers.us/IGCSE/Maths/CIE/2009%20Nov/0580_w09_qp_4.pdf
2)iv) I know its a shear, i know the invariant line is the y-axis, i thought the shear factor was 1 (4/4=1). But the answer says -1. Why? >.< >.<

By the way.. for probability, we can simplify the fraction right? cuz the calculator just gives u the simplest form and its easier...

[ivrytwr3]

Can someone explain how you do this one? (i know it's meant to be easy, but i haven't looked at how to do these )

Write down the gradient of the line y=3x-4

and then:

Write down the equation of a line through (0,0) parallel to y=3x-4

thanks!

[Dibss]

for probability, we can simplify the fraction right? cuz the calculator just gives u the simplest form and its easier...

yep, it's actually better if you simplify!

[Ghost Of Highbury]

Can someone explain how you do this one? (i know it's meant to be easy, but i haven't looked at how to do these )

Write down the gradient of the line y=3x-4

and then:

Write down the equation of a line through (0,0) parallel to y=3x-4

thanks!

y = mx + x

m = gradient

y = 3x-4

m = 3 = gradient.

parallel to y=3x-4 means that it has the same gradient = 3

y = 3x+c

wen x = 0, y = 0 (0,0)

0 = 3*0 + c
0 = 0 + c

c = 0

y = 3x

[33oomar]

The principal amount is the one you invest.

The formula for compound interest, P(1+r/100)^t, is when, P is principal amount, r, the rate, and t, the time.

If the rate is yearly, then the time, t, must too be in years.
If the rate is monthly, the time, t, must be monthly too.

The answer you get to the formula above IS NOT THE INTEREST. It is the TOTAL AMOUNT.

If you invest 200, and the answer you get to the formula is 300, the 300 is not the interest, rather the TOTAL you get.

The interest is, total - principal, 300 - 200 = 100.

Thanks alot dude you really saved my A** 

[Adzel]

Is there any transformation, hitogram and line grahs in paper2

[Shazizzzle]

Umm, in Q21, Oct/Nov 2000, PQR, in (a), is 54.0 deg.
But, they say the obtuse angle.
So, does that mean the larger PQR?
That would be 360 - 54.0.
OR, do they mean obtuse, as in, using the Quadrant II law, 180 - x = 180 -54.0?

[Ghost Of Highbury]

they mean the quadrant law, 180-54.

[Shazizzzle]

Is there any transformation, hitogram and line grahs in paper2

Yes. All three.

Transformation, usually relating to smaller Qs. i.e reflection and rotation etc.
They just ask you to identify the transformation and the matrix.

Line graphs, yes... For calculating gradients. And in linear programming to find a required region by shading.

Histogram, indeed there is, when half is drawn, the other half you have to complete, and usually complete a table.

[Vin]

I hate HISTOGRAMS .. !!  somebody any tip for solving them ?? u wan me to post a paper ?? pls anything..

[Adzel]

Yes. All three.

Transformation, usually relating to smaller Qs. i.e reflection and rotation etc.
They just ask you to identify the transformation and the matrix.

Line graphs, yes... For calculating gradients. And in linear programming to find a required region by shading.

Histogram, indeed there is, when half is drawn, the other half you have to complete, and usually complete a table.

Do you remember which past papers contain them ...me too