Q&A - P3 Math

[paranoid mum]

hi all.


I need help with my son's P3 Q from past year exam papers 2010

A skirt & a dress cost $155
A skirt & a pair of pants costs $95
A skirt, a dress and a pair of pants cost $300
How much is the skirt?

The answer was $50.

But i was wondering if the skirt is $50, when i add up the rest it does not tally to $300?.. hmn..

Would appreciate if any one can help with this. Thanks much!

[taolao]

It's because the last question is wrong

A skirt, a dress and a pair of pants should cost $200
Then you will get the skirt at 50

155 + pants = 200--> pants = 45
skirt + pants = 95-->skirt = 50

paranoid mum:

hi all.

I need help with my son's P3 Q from past year exam papers 2010

A skirt & a dress cost $155
A skirt & a pair of pants costs $95
A skirt, a dress and a pair of pants cost $300
How much is the skirt?

The answer was $50.

But i was wondering if the skirt is $50, when i add up the rest it does not tally to $300?.. hmn..

Would appreciate if any one can help with this. Thanks much!

[Dharma]

24hr-mum:

ben is an office boy who works in a building where every floor has a lift


his routine begins when he leaves his office and takes the lift 9 floors up to Mr Tan's office. He then goes to Mrs Wong''s office 5 floors below Mr Tan's office to collect a parcel.
Next, he takes the lift 15 floors up to hand the parcel to Miss Lee. After that, he takes the lift 20 floors down back to the first floor. On which floor is Ben's office located?


is the answer 1st or 2nd floor?
is Miss Lee on 20th floor, Mr Tan on 10th floor and Mrs Wong on 5th floor?

Working backwards
1 + 20 – 15 + 5 – 9 = 2

Ben’s office is on the 2nd floor

[24hr-mum]

thanks!

this made it much easier to understand

[24hr-mum]

A+B+C=37

A+B+B=32
A+A+B=28

what is C?

[imacsg]

24hr-mum:

A+B+C=37/

A+B+B=32
A+A+B=28

what is C?

Let Me try:
3A + 3B = 60
so A + B = 60/3 = 20
then C = 37 -20 =17

Hope U understand.

[Florence88]

The ratio of the number of marbles to the number of mosiac was 4 : 5. After some mosaic were added, 40% of the new total were mosaic. What was the percentage increase in the number of mosaic

[James Ang]

Florence88:

The ratio of the number of marbles to the number of mosiac was 4 : 5. After some mosaic were added, 40% of the new total were mosaic. What was the percentage increase in the number of mosaic

Something seems wrong with this question.

Before ratio
Marble : Mosaic
4:5
= 12:15

After ratio
6:4
= 12:8

The number of mosaic in fact decrease if the marbles are the same.

[Florence88]

Apology, whether question should be :


…40% of the new total were marbles…
[/b]

[Florence88]

Apology, whether question should be :


…40% of the new total were marbles…
[/b]