firefly38:

cimman:

[quote=\"firefly38\"]Hi cimman.. Will you be conducting any Math workshop for P5 any time this year ? Thank you..

wow, you are a night bird. I do intend to have one more workshop before the year is up. It will be after the PSLE as this is not the time to introduce new concepts to P6 students.

Ya.. I am an owl..

May I ask at which thread will you announce the details of your workshop, so that I can keep a lookout then ? Thanks again..[/quote]:). someone after my own heart.
look for it in the Happening thread. or you can send me a PM with your email and contact number, and I'll notify you when the time comes.

firefly38:

Hi cimman.. Will you be conducting any Math workshop for P5 any time this year ? Thank you..

wow, you are a night bird. I do intend to have one more workshop before the year is up. It will be after the PSLE as this is not the time to introduce new concepts to P6 students.

haven't logged in for a few days, and there's all these interesting discussions

while it is true, that the context is not aligned with the values, the takeaway from this problem is that that the student should be able to solve problems that incorporates 3 concepts:
(1) Transfer Concept (Before/After)
(2) Double If Concept
(3) Unit value or Grouping concept

(3) The Unit Value concept is present here because there are 2 different unit value types: (a) $ (money) (b) number of days
as such, conversion is needed between one unit value type to another. This involves a multiplication operation. In the solution below, all values are converted to Total $ value type.
The formula for Unit Value problem is: Unit Value x Quantity = Total $ Value
in this case, Quantity = number of days, Total Value = amount ($) spent

(2) The Double If Concept has a hidden inference. The Before values of the 1st If case is the same as the Before values of the 2nd If case. This will give us an additional equation to work with.

(1) Transfer Concept: the formula for solving Transfer type problems is: Before + Transfer = After
The solution below incorporates all these 3 different concepts in a tabular form.

-----------------------------------------------------------------------------------

Father has given Claire and Jane each a certain amount of money to spend. If Claire spends $30 each day and Jane spends $20 each day, Claire would have $100 left by the time Jane spends all her money. If Claire spends $20 each day and Jane spends $30 each day, Claire would have $580 left by the time Jane spends all her money. Find the amount of money given to each of the girls.

Using Table Heuristics technique, we first, transfer the values from the problem sum to the table, note that all values in the table are expressed in Total $ value type:
let u = number of days in the 1st If case
let p = number of days in the 2nd If case

http://i43.tinypic.com/4rvnfc.png\">

next, using the Double If inference, we circle the 2 Before values, as they are the same values.
Note that it is important to write the answer down in terms of u or p before working out the detail solution. This is to keep the focus on finding the relevant variable and avoid careless mistakes in the final stages.

http://i43.tinypic.com/30c4pw3.png\">

mummyscopio:

oic....

i kept thinking that there is gaps in between the cones....
like this

^---^---^
|--60cm--|


/ \\---/ \\---/ \\---/ \\
|-----------200cm------|

thank you so much

actually, it doesn't matter if there are gaps between the cones or if the cones occupy the entire space.
The question stated that \"The length occupied by 3 small cones and 4 big cones are 60cm and 200cm respectively.\"
This means that 3 cones occupy a space of 60cm. There are 2 scenarios that this can happen and they are illustrated below:
http://i42.tinypic.com/nh06yc.png\">
Both scenarios satisfy the stated condition. You might ask: what about the gap between the green cones ? the question did not give any information on the gap, so it is dead space, ie. nothing can occupy that gap. As such, the solution remains the same, whether you're using the green cone scenario or the blue cone scenario.

to put it another way, 3 parking lots occupy 18 meters. There are 3 cars in the 3 parking lots. It doesn't matter if the car is a long station wagon or small VW Beetle.
http://i43.tinypic.com/qzki2h.png\"> 3 stations wagons occupy 18 meters.


http://i44.tinypic.com/15nvexf.png\"> 1 station wagon and 2 VW Beetles occupy 18 meters.

Each car park lot is 6 meters or 6 meters is allocated for each car park lot. It doesn't matter if it is a large car or a small car that occupies the lot. Once the space is allocated, nothing can come in to take that extra space unless the question explicitly says otherwise.

The question specifies the allocation of space for 3 cones. Whether the cones fills up the space allocated or not, is immaterial.

pensiveowl:

Hi.. could someone pls help with this question:


http://www.positivelyquit.org/images/temp/HP2012.jpg\">

Thanks

http://i40.tinypic.com/2u8ukuh.png\">

first we draw 2 squares and a diagonal across:
http://i44.tinypic.com/2a9y9mh.png\">

next, we break the large square into 4 smaller squares:
http://i39.tinypic.com/2dspuo0.png\">

we find that the diagonal cuts across the exact center of the shape, we now have symmetry:
http://i42.tinypic.com/23wv4nq.png\">

we now superimpose a semicircle on the squares:
http://i43.tinypic.com/2v3ix3b.png\">

http://i39.tinypic.com/jttnaw.png\">

http://i42.tinypic.com/2gub32w.png\">

http://i41.tinypic.com/ibml3a.png\">

an alternative way is to recognize common shapes:
to find the green area, it is the area of the triangle - the blue area
http://i43.tinypic.com/2s6r4lk.png\">

the blue area is a common shape, it's what I call a cornice shape, quite common in a lot of shaded area questions:
http://i43.tinypic.com/j7ri9y.png\">

it's area is found by : (area of square - area of circle) /4
http://i42.tinypic.com/2lse39v.png\">

Michaelia0816:

Speed Question:

Train A and Train B leaves the same station at the same time heading towards the east direction. Train A travels 65 km at an average speed of 40 km/h and then travels another 25 km at an average speed of 20 km/h before reaching its destination. Train B also travels 40 km at an average speed of 25 km/h and stops for a 34 minutes break before continuing its journey. How fast should Train B travel after the 34 minutes break in order to reach the same destination as Train A at the same time?

http://i43.tinypic.com/kt5y8.png\">

Map the distance time diagram to the table. If your child can visualize using the table alone, that will be more efficient.
http://i42.tinypic.com/20r1nqp.png\">

while there are 3 equations, they are not simultaneous equations. They can be solved in a sequential manner. I call them sequential equations. It gives the entire solution at a glance. The execution of that solution can then be done in a sequential manner.

ngl2010:

cimman:

[quote=\"James Ang\"]http://i40.tinypic.com/z4ifn.jpg\">

this question was answered before:
http://www.kiasuparents.com/kiasu/forum/viewtopic.php?f=69&t=280&start=6320

I don't think the answer is correct :?[/quote]the values are different, but the principle is the same.

cimman:

James Ang:

http://i40.tinypic.com/z4ifn.jpg\">

http://i42.tinypic.com/dyug69.png\">

http://i44.tinypic.com/2mjp03.png\">

http://i44.tinypic.com/124tqbb.png\">

http://i44.tinypic.com/20h3ls4.png\">

James Ang:

http://i40.tinypic.com/z4ifn.jpg\">

this question was answered before:
http://www.kiasuparents.com/kiasu/forum/viewtopic.php?f=69&t=280&start=6320

carol73:

alice folder some paper cranes. she gave bob 60 cranes and 1/7 of the remaining one. Alice than gave David 56 of her cranes and 1/4 of the remainder. bob and david receive the same number of cranes from alice. how many cranes did Alice have at first?

Step 1: transfer the values from the problem sum to the table
http://i43.tinypic.com/2i6nzvr.png\">

Step 2: fill in the blank boxes and circle the equations. In Remainder type problems, the After value of the 1st activity = Before value of the 2nd activity.
http://i42.tinypic.com/az9apt.png\">