Maths, Addmaths and Statistics: Post your doubts here!

[TheStallion-Reborn]

This happens due to premature rounding off.

can u please xplain it a bit> ?

 

[danial 234]

do ur working with 4 significant figures. and write ur ans with 3 sig fig. otherwise ur answer would be rejected

can u please xplain it a bit> ?

 

[TheStallion-Reborn]

do ur working with 4 significant figures. and write ur ans with 3 sig fig. otherwise ur answer would be rejected

and this applies to EVERYTHING?? including the values for trignometrical ratios?

 

[AbbbbY]

can u please xplain it a bit> ?

Keep 4SF through out and round of only at the very end when giving the answer (to whatever he requires, 3sf or 3dp)

 

[danial 234]

and this applies to EVERYTHING?? including the values for trignometrical ratios?

to everything except angles. the angles should be given till first dp

 

[farhan141]

try to reset ur calculator. Maybe ur calculator is set on radians instead of degree

It's not that much difference, just between decimals. I already tried resetting it, then I bought the latest one and it works fine.

 

[TheStallion-Reborn]

to everything except angles. the angles should be given till first dp

alryt.. thankies

 

[danial 234]

this rule is clearly stated at the start of paper and examiner report

 

[TheStallion-Reborn]

Keep 4SF through out and round of only at the very end when giving the answer (to whatever he requires, 3sf or 3dp)

do ur working with 4 significant figures. and write ur ans with 3 sig fig. otherwise ur answer would be rejected

how do i do it???????? do u guys also write down every value in each step on the paper, writing it into 4 sig figures and then putting the 4 sig figures in the next step?? wont it deprive me of time? or do u guys carry on wit what the calculator displays??

 

[danial 234]

i

how do i do it???????? do u guys also write down every value in each step on the paper, writing it into 4 sig figures and then putting the 4 sig figures in the next step?? wont it deprive me of time? or do u guys carry on wit what the calculator displays??

it is better to follow this rule for examiner reports lay stress on this point and many good students have lost marks due to this. as for me i follow this rule and still have plenty of time to revise

 

[AbbbbY]

how do i do it???????? do u guys also write down every value in each step on the paper, writing it into 4 sig figures and then putting the 4 sig figures in the next step?? wont it deprive me of time? or do u guys carry on wit what the calculator displays??

There's ample of time in O Level Math.
I did my entire paper with pencil first, rechecked, wrote it in pen and erased.

I used to write the important steps only and do a two-three steps in one (ofcourse, without omitting the necessary stuff, if for example, I need the nature of the stationary point, I can't skip dy/dx going sraight into d^2y/dx^2

And no. Don't carry on with what the calc displays. Round it off to 4sf and carry on with that.

 

[mohdumar]

a tank can be filled by two pipes in one hour and 20 minutes.if the two pipes are to fill the tank individually the smaller pipe will take two more hours more than the bigger piper to do so.find the time each pipe will take to fill the tank differently??? plzz solve n help?!

here u go . asnwers are in minutes

 

[TheStallion-Reborn]

can sum1 please help me with question 5 part d?
http://papers.xtremepapers.com/CIE/...Calculator Version) (4024)/4024_w12_qp_21.pdf

 

[areela hassan]

thaaaaankyoouuu this helped a lot

here u go . asnwers are in minutes

 

[danial 234]

can sum1 please help me with question 5 part d?
http://papers.xtremepapers.com/CIE/Cambridge International O Level/Mathematics D (Calculator Version) (4024)/4024_w12_qp_21.pdf

first, divide the square into quadrants, find area o quadrant 19.63. then divide the top right hand side oval shape into two. in this way quadrant would become a triangle and a half oval. then calculate area of triangle 12.5. subtract the area of tri from quad to get area of half oval. 7.13. then find area of semi circle. 39.27.ssubtract the area of one oval from it to get ans. 39.27-2(7.13) = 25

 

[danial 234]

can anyone help me with q 9 b i a
http://papers.xtremepapers.com/CIE/...Calculator Version) (4024)/4024_s10_qp_21.pdf

 

[Suchal Riaz]

Somebody please check my histogram and cumulative frequency curve from the values in table.
Saad Mughal

 

[Saad Mughal]

You're histogram is confusing, it doesn't have proper frequency density, what class width did you take?
The last bit in the histogram 60-70 is extended to 75, correct that too.
The cumulative curve is fine.

 

[Suchal Riaz]

You're histogram is confusing, it doesn't have proper frequency density, what class width did you take?
The last bit in the histogram 60-70 is extended to 75, correct that too.
The cumulative curve is fine.

what do u mean by 'i took'? the class width for 35-40 wont be 5 or we can change it?
how is it confusing?

 

[Saad Mughal]

what do u mean by 'i took'? the class width for 35-40 wont be 5 or we can change it?
how is it confusing?

Just use the class widths that are given. You've divided them incorrectly. Using this you're frequency densities should be:
35-40 : 3
40-45 : 4
45-50 : 6
50-55 : 7
55-60 : 5.6
60-70 : 1.2
The last 4 are correct, just make the correction to the size of the last block and to the first two frequency densities, you're graph will be perfect then.