Q&A - PSLE Math

[moonsun]

MathIzzzFun:

moonsun:

Hello.


Would be thankful if someone can teach me how I can solve this...

If 1/5 = 1/A + 1/B and A & B are whole numbers, what are the values of A & B?

1/5 = 1/5 - 1/6 + 1/6 = 1/30 + 1/6

cheers.

Hi Mathizzzfun,

Thank you for the workings.

But.... Sorry, how did you get 1/5-1/6 + 1/6?.... :nailbite:

[MathIzzzFun]

moonsun:

MathIzzzFun:

[quote=\"moonsun\"]Hello.


Would be thankful if someone can teach me how I can solve this...

If 1/5 = 1/A + 1/B and A & B are whole numbers, what are the values of A & B?

1/5 = 1/5 - 1/6 + 1/6 = 1/30 + 1/6

cheers.

Hi Mathizzzfun,

Thank you for the workings.

But.... Sorry, how did you get 1/5-1/6 + 1/6?.... :nailbite:[/quote]this is a common \"trick\" taught to MO students to solve questions like :
1/2 ( 1 + 1/3 +1/6 + 1/10 + 1/15......+1/5050)

cheers.

[MathIzzzFun]

thoughtfulminds:

Zai ah MathIzzFun !


Are you a teacher?

math tutor .. cheers.

[mama_10]

Hi,


Need help for below question.
There were 50 questions in a Maths test. Sam answered 85% of them correctly while Nicky answered 80% of them correctly. How many percent more questions did Sam answer correctly than Nicky ?

My kid said how come Sam answered 42.5 question correctly?

Thank you.

[MathIzzzFun]

mama_10:

Hi,


Need help for below question.
There were 50 questions in a Maths test. Sam answered 85% of them correctly while Nicky answered 80% of them correctly. How many percent more questions did Sam answer correctly than Nicky ?

My kid said how come Sam answered 42.5 question correctly?

Thank you.

..cute... well, it is possible that Sam answered part 1 of a 2-part question correctly. Since the question is on percentage, the total number of questions is not important. The question can be changed to :

\"In a Maths test. Sam answered 85% of them correctly while Nicky answered 80% of them correctly. How many percent more questions did Sam answer correctly than Nicky ?\"

cheers.

[mama_10]

Haha!

My kid can get al the paper 2 questions correct but make careless mistake on multiple choice.
How to ‘cure’?
btw, what’s the answer for that question?
Thank you.

[MathIzzzFun]

mama_10:

Haha!

My kid can get al the paper 2 questions correct but make careless mistake on multiple choice.
How to 'cure'?
btw, what's the answer for that question?
Thank you.

(Sam's score - Nicky's score)/Nicky's score x 100%

= (85%-80%)/80% x 100%

= 6.25%

cheers.

[mummyv]

MathIzzzFun thanks for the link to the earlier ques I posted.


Pls help with this question.

ABCD is a square. There are 2 smaller squares shaded in grey inside ABCD. Express the shaded squares as a fraction of ABCD. Thanks http://i49.tinypic.com/2eumkwj.jpg\">

[mama_10]

Hi MathIZZZFun,


Thanks! we got the same answer too.

[MathIzzzFun]

mummyv:

MathIzzzFun thanks for the link to the earlier ques I posted.


Pls help with this question.

ABCD is a square. There are 2 smaller squares shaded in grey inside ABCD. Express the shaded squares as a fraction of ABCD. Thanks http://i49.tinypic.com/2eumkwj.jpg\">

Can u re-post the pic, not visible.......thkq

cheers