Mathematics: Post your doubts here!

[Fayax555]

Can someone help me with this easy yet confusing questn?

A man spends 1/3 of his salary on housing and 2/5 of the remaining on food. What fraction is left for other purposes?

You can do this question, just like you do in probability. When you add those all fractions, it will be equal to 1.
ans: 1-(1/3)-(2/5).
final answer is _____

 

[snailey]

You can do this question, just like you do in probability. When you add those all fractions, it will be equal to 1.
ans: 1-(1/3)-(2/5).
final answer is _____

I know I did it that way but the answer in markscheme says its wrong.

 

[Kdown567]

He spends 1/3 on accommodation, so he has 3/3 - 1/3 = 2/3 left over.

Of that remaining 2/3, he spends 2/5 on food. To figure out how much 2/5 of 2/3 is, you multiply them.

2/5 of 2/3 = 2/5 x 2/3

To multiply fractions, simply multiply the denominators and numerators of the respective numbers.
2/5 x 2/3 = 4/15

So he spent an additional 4/15 of his total salary on food.

To find out how much he has left subtract 2/3 - 4/15.

But wait, the denominators don't match! Simply multiply 2/3 by 5/5 to get 15 as a denominator. This is the same essentially multiplying by 1, which does not change the value of the number.
2/3 x 5/5 = 10/15

Now we can subtract 10/15 - 4/15 = 6/15

Since both numerator and denominator are factors of 3, you can divide both by 3 to simplify the fraction
6/15 = 2/5

After food and accommodations, he has 2/5 of his initial salary.






Not my work by the way haha found it when I wanted to check my answer

 

[Fayax555]

I know I did it that way but the answer in markscheme says its wrong.

Can you give me a link to the paper or can you give me the subject code, year and paper no.

 

[Kdown567]

Can you give me a link to the paper or can you give me the subject code, year and paper no.

+1

 

[snailey]

He spends 1/3 on accommodation, so he has 3/3 - 1/3 = 2/3 left over.

Of that remaining 2/3, he spends 2/5 on food. To figure out how much 2/5 of 2/3 is, you multiply them.

2/5 of 2/3 = 2/5 x 2/3

To multiply fractions, simply multiply the denominators and numerators of the respective numbers.
2/5 x 2/3 = 4/15

So he spent an additional 4/15 of his total salary on food.

To find out how much he has left subtract 2/3 - 4/15.

But wait, the denominators don't match! Simply multiply 2/3 by 5/5 to get 15 as a denominator. This is the same essentially multiplying by 1, which does not change the value of the number.
2/3 x 5/5 = 10/15

Now we can subtract 10/15 - 4/15 = 6/15

Since both numerator and denominator are factors of 3, you can divide both by 3 to simplify the fraction
6/15 = 2/5

After food and accommodations, he has 2/5 of his initial salary.






Not my work by the way haha found it when I wanted to check my answer

OMG! God, thanks thats the right answer! 2/5 it is
Where did u get it from haha?

 

[snailey]

Can you give me a link to the paper or can you give me the subject code, year and paper no.

Actually it was from a math text book by David Rayner.

 

[snailey]

One more sum you guyz!
A prize is divided between 3 people X, Y and Z. If the ratio of X's share to Y's share is 3:1 and Y's share to Z's share is 2:5, calculate the ratio of X's share to z's share.




Thanks guys, you are being really helpful

 

[Kdown567]

One more sum you guyz!
A prize is divided between 3 people X, Y and Z. If the ratio of X's share to Y's share is 3:1 and Y's share to Z's share is 2:5, calculate the ratio of X's share to z's share.




Thanks guys, you are being really helpful

X:Y Y:Z

3:1 2:5

Both ratios contain Y, so what we want to do is make Y the same in both equations. Let’s make the Y on both sides equal 2.

X:Y Y:Z

6:2 2:5

Because Y is the same on both sides, we can now do this:

X:Y:Z

6:2:5

X:Z

6:5

 

[snailey]

X:Y Y:Z

3:1 2:5

Both ratios contain Y, so what we want to do is make Y the same in both equations. Let’s make the Y on both sides equal 2.

X:Y Y:Z

6:2 2:5

Because Y is the same on both sides, we can now do this:

X:Y:Z

6:2:5

X:Z

6:5

Thank u so much XD

 

[Kdown567]

any expected questions for on 2013 p2 or 4?

honestly I could give you a list of things that are more likely to show up than others but its almost impossible to predict

 

[sa1legend]

AsSalamoAlaikum Wr Wb...

Stuck somewhere in Maths?? Post your queries here! Members around will help you InshaAllah.

NOTE: If you have any doubt in the pastpper questions, then kindly post the link to the paper!

May Allah give us all success in this world as well as the HereAfter...Aameen!!

SEQUENCES-Points to remember:
Many people find it hard, but to be honest it's just more of logic..that's all!

Sequences!

Using log for indices.

Hey I'm new to xtremepapers , so I though how bout you told me how the upper bound and the lower bound system in numbers work . I'm an Mathematics student doing paper 0580/22.

 

[Muskan Achhpilia]

I have a doubt-In many papers there is usually a question stating to find the transformation matrix represents a particular transformation. There is usually a diagram given with particular coordinates , so how do we form the matrix.It is usually in paper 4 0580 maths.

 

[snailey]

I have a doubt-In many papers there is usually a question stating to find the transformation matrix represents a particular transformation. There is usually a diagram given with particular coordinates , so how do we form the matrix.It is usually in paper 4 0580 maths.

There are fixed matrices for these type of transformations. I have a booklet kind of thing named "Essential Revision" which has all the formulas and stuff. it also has a page where all the representing matrices are given. How should I send you that?

 

[Muskan Achhpilia]

If you can just send it to me on my mail id it will be great-
[email protected]

Furthermore, if it is a rotation clockwise 60 degrees or something like that then how do i solve it?

 

[Kdown567]

.

I have a doubt-In many papers there is usually a question stating to find the transformation matrix represents a particular transformation. There is usually a diagram given with particular coordinates , so how do we form the matrix.It is usually in paper 4 0580 maths.

 

[Muskan Achhpilia]

.

Thank you so much for your help but like i previously mentioned if it is a rotation clockwise 60 degrees or something like that then how do i solve it?

 

[Kdown567]

Thank you so much for your help but like i previously mentioned if it is a rotation clockwise 60 degrees or something like that then how do i solve it?

Highly unlikely they'll ask you for an oddity such as 60* http://m.wolframalpha.com/input/?i=rotate+60+degrees

However the use of 90 both anti and clockwise as well as 180* is very common , (and covered in the sheet)

 

[Muskan Achhpilia]

Highly unlikely they'll ask you for an oddity such as 60* http://m.wolframalpha.com/input/?i=rotate 60 degrees

However the use of 90 both anti and clockwise as well as 180* is very common , (and covered in the sheet)

Oh alright, thanks!

 

[Saket Sekhsaria]

The Picture Displays my Problem. I found the answer but i do not understand why and need a bit of explaining.
Thanks in advance