Q&A - PSLE Math

[david59]

Mary Joy:

please help me with these questions thank you


2.Jim bought some chocolates and gave half of them to ken.ken bought some sweets and gave half of them to Jim.Jim ate 12 sweets and ken ate 18 chocolates.after that the Number of sweets and chocolates Jim had were in the ratio 1:7 and the number of sweets and chocolates ken had were in the ratio. 1:4

How many sweets did ken buy?

This is another method of solving this problem sum. Hope it is explained clearly to you. God bless.


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[MathIzzzFun]

Mary Joy:

Please help me to answer this question


David and his brother John decided to cycle from his home to the library using the same route. They started cycling at the same time. David cycled at a speed of 15km/hr. Both of them did not change their speed throughout the race . When John covered 1/3 the distance , David was 4.5 km ahead of him.David reached the library at 4.45pm . What time did John reach the library?

assuming that David continues to cycle after reaching the library ...

for every 1/3 distance John cycles, David cycles 1/3 distance + 4.5km
--> John cycles 3/3 distance, David cycles 3/3 distance + 3 x 4.5 km

3 x 4.5 km = 13.5 km --> David would have cycled extra 13.5km when John reached the library

Time taken for David to cycle 13.5 km = 13.5/15 h = 0.9 h = 54 min

4.45 pm + 54 min --> 5.39 pm

John reached the library at 5.39pm

cheers.

[MathIzzzFun]

Mary Joy:

Please help me with this question!Thank you


In an auditorium,30% of the seats are reserved for the platinum class.The ratio of the number of seats for silver class to the number of seats for gold class is 12:13. After the auditorium underwent a renovation,the number of seats in the auditorium is increased by 20%. There are now 1440 seats reserved for the platinum class.

a) how many seats are reserved for the silver and gold class after the renovation?

b) how many seats are reserved for the silver class before the renovation?

After renovation, total number of seats --> 1440/0.3 = 4800
Before renovation, total number of seats --> 4800/1.2 = 4000

After renovation, total number of seats for silver and gold class --> 0.7 x 4800 = 3360

Before renovation, total number of seats for silver and gold class--> 0.7 x 4000 = 2800

Before renovation, silver class seats --> 12/25 x 2800 = 1344

cheers.

[Mary Joy]

MathIzzzFun:

Mary Joy:

Please help me to answer this question


David and his brother John decided to cycle from his home to the library using the same route. They started cycling at the same time. David cycled at a speed of 15km/hr. Both of them did not change their speed throughout the race . When John covered 1/3 the distance , David was 4.5 km ahead of him.David reached the library at 4.45pm . What time did John reach the library?

assuming that David continues to cycle after reaching the library ...

for every 1/3 distance John cycles, David cycles 1/3 distance + 4.5km
--> John cycles 3/3 distance, David cycles 3/3 distance + 3 x 4.5 km

3 x 4.5 km = 13.5 km --> David would have cycled extra 13.5km when John reached the library

Time taken for David to cycle 13.5 km = 13.5/15 h = 0.9 h = 54 min

4.45 pm + 54 min --> 5.39 pm

John reached the library at 5.39pm

cheers.

Thanks for ur time Mathizzfun...

[iCreative Math]

david59:

Mary Joy:

please help me with these questions thank you


2.Jim bought some chocolates and gave half of them to ken.ken bought some sweets and gave half of them to Jim.Jim ate 12 sweets and ken ate 18 chocolates.after that the Number of sweets and chocolates Jim had were in the ratio 1:7 and the number of sweets and chocolates ken had were in the ratio. 1:4

How many sweets did ken buy?

I have here another method to solve this same question recorded in YouTube. It takes only 7 minutes and I trust your child will be able to follow and understand the simplified problem-solving method.

Regards,
iCreative Math

YouTube Lesson Videos:

http://www.youtube.com/watch?v=kzPT1iIzaJk (PSLE Ratio Question)

[david59]

iCreative Math:

david59:

[quote=\"Mary Joy\"]please help me with these questions thank you


2.Jim bought some chocolates and gave half of them to ken.ken bought some sweets and gave half of them to Jim.Jim ate 12 sweets and ken ate 18 chocolates.after that the Number of sweets and chocolates Jim had were in the ratio 1:7 and the number of sweets and chocolates ken had were in the ratio. 1:4

How many sweets did ken buy?

I have here another method to solve this same question recorded in YouTube. It takes only 7 minutes and I trust your child will be able to follow and understand the simplified problem-solving method.

Regards,
iCreative Math

YouTube Lesson Videos:

http://www.youtube.com/watch?v=kzPT1iIzaJk (PSLE Ratio Question)[/quote]It is great that you have another method to solve certain questions. I have come across different students who have varying abilities to understand Maths. From my experience, majority are more able to understand using model method because they can see concepts better with pictorial images in front of them.
Usually only those with higher flair for Maths are able to understand and independently execute your concept to reason out the steps.
Thanks.

[iCreative Math]

David, fully agree. There are usually more than one possible method to solve most problem-sum questions, and which is better at times depends on the students’ strengths and aptitudes.


Over the years, I have found different students can have different thoughts patterns or processes, and hence correspondingly will better understand or prefer one method to another. For the more challenging 5-mark questions, it is good to offer them a choice of problem-solving methods, and encourage them to stick with one that suits them better.

Regards.

iCreative Math.

[MathIzzzFun]

david59:

Mary Joy:

please help me with these questions thank you


2.Jim bought some chocolates and gave half of them to ken.ken bought some sweets and gave half of them to Jim.Jim ate 12 sweets and ken ate 18 chocolates.after that the Number of sweets and chocolates Jim had were in the ratio 1:7 and the number of sweets and chocolates ken had were in the ratio. 1:4

How many sweets did ken buy?

This is another method of solving this problem sum. Hope it is explained clearly to you. God bless.


http://i43.tinypic.com/2z3uc6u.jpg\">

MD approach ..

http://i39.tinypic.com/a44d3t.png\">

cheers.

[oceanh2o]

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Hi , please help me in this question, thanks!

[Maths Hub]

oceanh2o:

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Hi , please help me in this question, thanks!

Hi,
Hint: AFE and CFD are both isosceles triangles (Lengths of square are all the same as the sides of the equilateral triangle)

Hope that helps!