Q&A - P3 Math

[wenray]

can a maths guru help me?


HOw do i solve these?

1.There are twice as many men as women at a party. After 15 women had left the party, the number of men in th party was thrice the number of the remaining women. How many adults attended the party?

2. A big ball has a mass of 8kg and a small ball has a mass of 4kg. The total number of big and small balls is 56 and their total mass is 280kg.
a) How many big balls are there?
b) How many small balls are there?

[corneyAmber]

wenray:

HOw do i solve these?


1.There are twice as many men as women at a party. After 15 women had left the party, the number of men in th party was thrice the number of the remaining women. How many adults attended the party?

http://i54.tinypic.com/wvpjxi.jpg\">

[corneyAmber]

wenray:

2. A big ball has a mass of 8kg and a small ball has a mass of 4kg. The total number of big and small balls is 56 and their total mass is 280kg.
a) How many big balls are there?
b) How many small balls are there?

This is not P3 Math, is it P4 or higher?

http://i56.tinypic.com/111uqzt.jpg\">

[wenray]

hi, these are P4 maths questions… is there a model that we can draw and understand?

[wenray]

sorry, i mean for qestion B. the balls question.

[corneyAmber]

Here you go...


http://i54.tinypic.com/dzjaxd.jpg\">

[usaik]

wenray:

2. A big ball has a mass of 8kg and a small ball has a mass of 4kg. The total number of big and small balls is 56 and their total mass is 280kg.
a) How many big balls are there?
b) How many small balls are there?

At P3, for this kind of question i think it may be easier for a child to answer via guess and check method. Just draw a table, divide 56 into half and start guessing & checking.
http://i56.tinypic.com/2dl9abn.jpg\">

[tianzhu]

wenray:

2. A big ball has a mass of 8kg and a small ball has a mass of 4kg. The total number of big and small balls is 56 and their total mass is 280kg.
a) How many big balls are there?
b) How many small balls are there?

Hi

This question is similar to those such as “Counting Heads and Legs” types.
P4 students should be familiar with questions like this one.

Lincoln visited a farm where he saw some cows and ducks. There were 75 of them. He then counted the legs of the animals and found that there were 220. How many animals of each type were there in the farm?

A common method to solve it is using a heuristics known as “ Making a Supposition” or “Assumption Method”

Assume that all the balls are of the small types, that is a mass of 4kg.

56x4 ------ 224
280 – 224 ------ 56

8 - 4 --------- 4

Number of big balls ------- 56/4 ------- 14
Number of small balls ------- 56 – 14 ------- 42

Best wishes

[wenray]

thanks all for your help!

[tianzhu]

cwc:

Hi Tianzhu,
Very curious, what do you use to produce all these fantastic diagrams/pics to explain?
Impressive :salute: How much time do you need to typically come up with one?

Hi cwc

Good Morning.

I am happy you liked my “masak masak” way of doing maths.

Just like any solutions in this forum, you’re correct to say that efforts are put in to post them.

I am a simple daddy, so I am not very conversant with IT. At times I need to play around with the software which I used in my solutions, which is PowerPoint in this case.

The usual process starts with coming up with some thoughts on the mathematical solutions to the questions. The thoughts are then translated into usually pictorial presentation which I hope will help students see that Maths is beautiful.

Best wishes