## Q&A - P3 Math

### Re: Q&A - P3 Math

Hi, not sure how to draw the model for this question. Pls help:

Q. May wanted to buy 6 pkts of cheese but was short of $2. If she buys 4 pkts of cheese, she will have $6 more. How much did she have at first?

School solution:

$6 + $2 = $8

6u - 4u = $8

2u = $8 ---> u = $4

4u = 4 x $4 = $16

4u + $6 = $16 + $6 = $22

May had $22 at first.

How to draw the model to explain this solution? Thanks!

BTW, is there a fixed formula for such questions? I realised that they just jump to the conclusion that 6u - 4u = $2 + $6 without first explaining that 6u - $2 = 4u + $6.

Q. May wanted to buy 6 pkts of cheese but was short of $2. If she buys 4 pkts of cheese, she will have $6 more. How much did she have at first?

School solution:

$6 + $2 = $8

6u - 4u = $8

2u = $8 ---> u = $4

4u = 4 x $4 = $16

4u + $6 = $16 + $6 = $22

May had $22 at first.

How to draw the model to explain this solution? Thanks!

BTW, is there a fixed formula for such questions? I realised that they just jump to the conclusion that 6u - 4u = $2 + $6 without first explaining that 6u - $2 = 4u + $6.

### Re: Q&A - P3 Math

cherrygal wrote:Hi, not sure how to draw the model for this question. Pls help:

Q. May wanted to buy 6 pkts of cheese but was short of $2. If she buys 4 pkts of cheese, she will have $6 more. How much did she have at first?

School solution:

$6 + $2 = $8

6u - 4u = $8

2u = $8 ---> u = $4

4u = 4 x $4 = $16

4u + $6 = $16 + $6 = $22

May had $22 at first.

How to draw the model to explain this solution? Thanks!

BTW, is there a fixed formula for such questions? I realised that they just jump to the conclusion that 6u - 4u = $2 + $6 without first explaining that 6u - $2 = 4u + $6.

### Re: Q&A - P3 Math

Thank you

Mr. Siva has 240 pens. He has 25 more purple pens than black pens. He has 40 fewer red pens than black pens. How many red pens does he have?

Mr. Siva has 240 pens. He has 25 more purple pens than black pens. He has 40 fewer red pens than black pens. How many red pens does he have?

### Re: Q&A - P3 Math

jolenekoh wrote:Thank you

Mr. Siva has 240 pens. He has 25 more purple pens than black pens. He has 40 fewer red pens than black pens. How many red pens does he have?

Is the answer 45 ?

### Re: Q&A - P3 Math

peggy wrote:jolenekoh wrote:Thank you

Mr. Siva has 240 pens. He has 25 more purple pens than black pens. He has 40 fewer red pens than black pens. How many red pens does he have?

Is the answer 45 ?

Sorry...I don't have the answer woh

- smartmummy
- KiasuGrandMaster
**Posts:**4938**Joined:**Thu May 19,**Total Likes:**2

### Re: Q&A - P3 Math

jolenekoh wrote:Thank you

Mr. Siva has 240 pens. He has 25 more purple pens than black pens. He has 40 fewer red pens than black pens. How many red pens does he have?

### Re: Q&A - P3 Math

Smartmummy

smartmummy wrote:

Mr. Siva has 240 pens. He has 25 more purple pens than black pens. He has 40 fewer red pens than black pens. How many red pens does he have?

### Re: Q&A - P3 Math

A group of 30 students attended a course.

18 of them attended the morning lesson and 24 of them attended the afternoon lesson. How many students attend both the morning and afternoon lessons?

18 of them attended the morning lesson and 24 of them attended the afternoon lesson. How many students attend both the morning and afternoon lessons?