Q&A - PSLE Math

[dovetail]

bobsg01:

Math problem.


Thanking in advance for the help.

http://i53.tinypic.com/4g2ekx.jpg\">

Rachel. XXX
Ronnie. XXX|XXX|XXX|450| if he spends thrice as much
Ronnie. X|-------690-------| if he spends one third as much


8 units ---> 690-450 = 240
1 unit ---> 30


Given to Ronnie --> 9 units + 450 = 270+450 = 720
Given to Rachel ---> 3 units = 90

[stary]

bobsg01:

Thank you stary for the solution.

Glad to help

[bobsg01]

Thank you stary for the solution for Q16.


Need one understanding from you:

1 / 3 so you draw XXX

8 units => unable to catch how did you calculate this?

[dovetail]

bobsg01:

Thank you stary for the solution for Q16.


Need one understanding from you:

1 / 3 so you draw XXX

8 units => unable to catch how did you calculate this?

At first, Rachel only has 1 section, Ronnie has 3 sections + 450.

If Ronnie spent 1/3 as much, you have to divide Rachel's 1 section to 3 sections so she has XXX and Ronnie has X.

Ronnie's 3 section becomes 9 units (or 9 X's).

His leftover: 8 units + 450 = 690,
so 8 units = 240, and so on....

[stary]

Thanks doevetail for helping me answering bobsg01's question for me

[stary]

Hi all,


Have a question here...

73A x B = 4428
What is the value of A + B? :?:

[ozora]

Need guide n help on the following questions.

q1. I had some red and blue stickers. If 72 red stickers were removed, the ratio of the number of red stickers to blue stickers would be 1:2. If 180 blue stickers were removed, the ratio of the number of red stickers to blue stickers would be 5:1. How many red stickers were there at first?

q2.There were 2 identical flights of steps.For the 1st flight of steps , Samuel walked up some steps and ran 7 steps in 67seconds. For the 2nd flight of steps, Samuel walked up some steps and ran 15 steps in 43seconds. How long will Samuel take to walk up both flight of steps?

q3) 2 candles, S and T have different lenght and thickeness. Candle S can burn for 8 hours while Candle T can burn for 4 hours. Both candles are lighted at the same time. After 2 hours, they had the same length left. Find the ratio of the initial length of Candle S to initial length of Candle T .

[bobsg01]

Thank you dovetail for the explanation. http://i53.tinypic.com/34yqphc.jpg\">

[MathIzzzFun]

stary:

Hi all,


Have a question here...

73A x B = 4428
What is the value of A + B? :?:

Hi

A=8, B = 6, A+B = 14

cheers.

[MathIzzzFun]

ozora:

Need guide n help on the following questions.

q1. I had some red and blue stickers. If 72 red stickers were removed, the ratio of the number of red stickers to blue stickers would be 1:2. If 180 blue stickers were removed, the ratio of the number of red stickers to blue stickers would be 5:1. How many red stickers were there at first?

q2.There were 2 identical flights of steps.For the 1st flight of steps , Samuel walked up some steps and ran 7 steps in 67seconds. For the 2nd flight of steps, Samuel walked up some steps and ran 15 steps in 43seconds. How long will Samuel take to walk up both flight of steps?

q3) 2 candles, S and T have different lenght and thickeness. Candle S can burn for 8 hours while Candle T can burn for 4 hours. Both candles are lighted at the same time. After 2 hours, they had the same length left. Find the ratio of the initial length of Candle S to initial length of Candle T .

Hi

Q3. After 2hours, length remaining are:
Candle S = 6/8 S = 3/4 S,
Candle T = 2/4 T = 1/2 T, S and T are the initial length of the candles.

3/4 S = 1/2 T
S/T =4/6 = 2/3

Ratio of initial length of Candle S to Candle T = 2 : 3

cheers.