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[CJM]

A pond can be filled in 1h by 6 taps following at the same rate. How long will it take for 4 such taps to fill the pond?

[Belle2011]

CJM:

A pond can be filled in 1h by 6 taps following at the same rate. How long will it take for 4 such taps to fill the pond?

1 tap can fill 1/6 pond in an hr.
4 taps can fill 4/6 pond in an hr.
4 taps can fill 2/6 pond in 30 min.
Thus 4 taps can fill 1 pond in 1hr 30 min.

:roll:

[ADoc]

Emelyn:

Hi all,


Need some help here.

Qn : Jan and Kay had equal number of sweets and equal number of chocolates. Jan ate 12 sweets and Kay ate 18 chocolates and then the ratio of Jan's sweets to chocolates became 1:7, and the ration of Kay's sweets to chocolates became 1:4. How many sweets did Jan have at first ?

Many thanks.

Hi Emelyn! I have posted the solution to this question before. Pls refer to the link. cheers!

http://www.kiasuparents.com/kiasu/forum/viewtopic.php?t=6373&postdays=0&postorder=asc&start=3220

[small]

Emelyn:

Hi all,


Need some help here.

Qn : Jan and Kay had equal number of sweets and equal number of chocolates. Jan ate 12 sweets and Kay ate 18 chocolates and then the ratio of Jan's sweets to chocolates became 1:7, and the ration of Kay's sweets to chocolates became 1:4. How many sweets did Jan have at first ?

Many thanks.

Please refer to Tianzhu's post for the solution.

http://www.kiasuparents.com/kiasu/forum/viewtopic.php?t=280&start=2620

[ozora]

trytry:

LaiHeng:

HI try try

thanks for the answer.
I am abit lost at : A: B
Ratio of no of group= 3: 2 . How do you derive=3: 2?

BOX............................................A.......................B
ratio of white beads in 1 gp.......2........................3

In Box A, every 2 beads in 1 gp.
................every 1bead in 1/2 gp
Similarly, in Box B, every 3 beads in 1 gp
......................... .every..1 bead in 1/3 gp

No of gp for 1 bead....................1/2.........................1/3
Express as a ratio....................1/2x6=3.................1/3x6=2
ratio of gp....................................3........................2

thanks
wow.. is really in dept understanding. How can kids do all these questions if they are not expose to it?

[she0407]

Pls help to explain.


When Gabriel bought 5 chairs, he had $12 left.
When he bought 9 such chairs, he was short of $60.
(a) Find the cost of each chair.
(b) How much money did he have?


Thank you very much!

[Brenda10]

she0407:

Pls help to explain.


When Gabriel bought 5 chairs, he had $12 left.
When he bought 9 such chairs, he was short of $60.
(a) Find the cost of each chair.
(b) How much money did he have?


Thank you very much!

Hi, the following is the working:

To buy 4 more chairs (9 -5), $72 would be needed (12 + 60).

9 - 5 = 4
60 +12 = 72
72 / 4 = 18

(5 * $18 ) + $12 = $102

Thank you

[CJM]

Belle2011:

CJM:

A pond can be filled in 1h by 6 taps following at the same rate. How long will it take for 4 such taps to fill the pond?

1 tap can fill 1/6 pond in an hr.
4 taps can fill 4/6 pond in an hr.
4 taps can fill 2/6 pond in 30 min.
Thus 4 taps can fill 1 pond in 1hr 30 min.

:roll:

thank u so much !

[Idont splat]

err... Can someone pls reply to my questions on page 328 ? :? Sorry if I was too impatient... :oops:

[yeonee]

ADoc:

yeonee:

[quote=\"Dharma\"]
144 = ( 2 x 2 x 2 ) x ( 2 x 3 x 3 ) = 8 x 18
Ben’s age now = 18
Ben’s younger brother’s age = 8
Ben’s age in 20 years’ time = 18 + 20 = 38

Sorry. Could u explain why (2x2x2) x (2x3x3)?

Hi Veonee! Dharma was using a more \"advanced\" concept of factorisation (versus guess & check) in order to find the two numbers that give 26 and 144 when added and multiplied together.

If you were to (prime) factorise 144 into its basic components, you will get
2 x 2 x 2 x 2 x 3 x 3. (start by dividing with 2, proceed to the next (prime) number, 3, when the quotient is no longer divisible by 2)

An alternative (and perhaps more intuitive) for primary students would be to write down all the factors of 144:
1, 2, 3, 4, 6, 8, 9, 12, 16, 18, 24, 36, 48, 72, 144
and find two numbers that add and multiply to give 26 and 144.[/quote]
OIC. Thank you very much.