Tutor MathsGuru: Ask me for your burning Maths questions!

[yeonee]

Dharma:

yeonee:

Need Help!


The sum of Ben's age and his younger brother's age is 26. The product of their ages is 144.
What is Ben's age in 20 years' time?

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)?

[ADoc]

yeonee:

Dharma:

[quote=\"yeonee\"]Need Help!


The sum of Ben's age and his younger brother's age is 26. The product of their ages is 144.
What is Ben's age in 20 years' time?

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)?[/quote]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.

[Idont splat]

Hi Everybody ... Pls help me to solve a few questions...

Been cracking my head but I still cant solve ..Having Maths CA test Tomorrow.. Sobz sobz...

1). Mr Tan brought some pens and pencils to the class.
If he gave away 4 pens and 1 pencils each time, there would be 78 pens left when all the pencils were given away. If 1 pen and 4 pencils were given away each time, there would be 153 pens left when all the pencils were given away. What was the total number of pens and pencils brought by Mr Tan.


2). Mr Tan had a total of $1741 in two safes. He transferred 5/9 of the money from Safe B to Safe A. Later, he transferred 3/5 of the money from Safe A to Safe B. In the end, he had $601 more in Safe B than
Safe A.
How much money did he have in Safe A then in Safe B at first??



3).386 children were in the hall watching the show \"Avatat\". Halfway through the show, 2/5 of the boys and 3/4 of the girls walked out, leaving 170 children in the hall. Find the number of boys who walked out from the hall.

Appreciate all your help..& many Thanks..

[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.

[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!