Tutor MathsGuru: Ask me for your burning Maths questions!

[Vanilla Cake]

YLH88:

4) Red Swastika SA1 2009 P2 Qn 17

The distance between Town P and Town Q was 480 km. At 10 30, Mr Poh left Town P travelling at a constant speed towards Town Q to meet his wife. At the same time, Mrs Poh who was at Town Q travelled towards Town P at a constant speed. Mr and Mrs Poh met each other at 14 30. Mrs Poh was travelling at 20 km/h faster than Mr Poh. What was the speed Mrs Poh was travelling at ?

20 x 4 = 80 km
(480-80)÷2 = 200 km

Distance travelled by Mr Poh = 200 km
Distrance travelled by Mrs Poh = 280 km

Speed at which Mrs Poh was travelling = 280÷4 = 70 km/h

YLH88:

5) Red Swastika SA1 2009 P2 Qn 9
Mr Fernandex drove from home to work at 60 km/h. After work, he needed to rush home for dinner and increased his speed on his way home by 30 km/h. As a result, he took 5 minutes less than what he had taken on his way to work. What was the distance between his house and office ?

Ratio of speed = 90 : 60 = 3 : 2
Ratio of time = 60 : 90 = 2 : 3

Time taken @ 90 km/h = 2 units
Time taken @ 60 km/h = 3 units
Difference in time taken = 5/60 = 1/12 hour = 1 unit

Distance travelled = 2 units x 90 km/h = 2x1/12x90 = 15 km
Distance between his house and office was 15 km

Mathsguru had posted her solution for this Fernandez's speed question recently. Pls wait for her to repost her solution again or you have to browse through this thread.
Thanks.

YLH88:

If the same set of questions have been posted before, would greatly appreciate if someone can point me to the pages.

Sorry, can't help due to the numerous pages in this thread and I have to study for my CT.
:imsorry:

[Herbie]

HI, Thanks MathsGURU


Can help with the qn below:

Belinda has 200 more books than Alan, Belinda gives 60% of her books to Alan. Alan then gives 25% of her books back to Belinda. In the end, Alan has 200 more books than Belinda. How many books does Belinda have at first?

Thanks!

[Vanilla Cake]

Herbie:

HI, Thanks MathsGURU


Can help with the qn below:

Belinda has 200 more books than Alan, Belinda gives 60% of her books to Alan. Alan then gives 25% of her books back to Belinda. In the end, Alan has 200 more books than Belinda. How many books does Belinda have at first?

Thanks!

Hi Herbie,
Your question is similar to this http://www.postimage.org/image.php?v=gxK_oj0 on Sat May 01, 2010 8:15 pm. Only the names are changed in your question but the concept applied to solve the question is the same.

Hope this helps while waiting for Mathsguru to repost her solution.

[YLH88]

Hi Vanilla Cake,


Sorry for the missing sentence in Qn 3 :oops:

Thank you so much for all the solutions !! All the best to your exam tomorrow.

[Dharma]

Herbie:

HI, Thanks MathsGURU


Can help with the qn below:

Belinda has 200 more books than Alan, Belinda gives 60% of her books to Alan. Alan then gives 25% of her books back to Belinda. In the end, Alan has 200 more books than Belinda. How many books does Belinda have at first?

Thanks!

Belinda gives 60% of her books to Alan
Belinda : 100u – 60u = 40u
Alan : 100u – 200 + 60u = 160u – 200

Alan gives 25% of his books to Belinda
Belinda : 40u + (40u – 50) = 80u - 50
Alan : 160u – 200 – (40u – 50) = 120u – 150

120u – 150 – (80u – 50) = 200
40u – 100 = 200
40u = 300
1u = 7.5

No. of books Belinda had at first = 100u = 750

[firebird]

Dear maths guru


Thank you for the answers

With best regards
firebird

[Herbie]

Thanks VC and Dharma Can help with the qn below?


There were some chairs in a school hall. 1/2 of the chairs were placed in short rows while 2/5 of the chairs were placed in long rows. The rest of th chairs were stacked at the back of the hall.

There were 15 short rows and long rows. If each short row contained 7 chairs less tha each kong rows, how many chairs were there in the wall altogether?

Tx

[Maths Monster]

delete

[Vanilla Cake]

Herbie:

Thanks VC and Dharma Can help with the qn below?


There were some chairs in a school hall. 1/2 of the chairs were placed in short rows while 2/5 of the chairs were placed in long rows. The rest of th chairs were stacked at the back of the hall.

There were 15 short rows and long rows. If each short row contained 7 chairs less tha each kong rows, how many chairs were there in the wall altogether?

Tx

Hi Herbie,
May I know the source of this question?

Maths Monster:

Can anyone can solve this without using guess and check method?

P6 SA1 2009 Paper2 Q14

Audrey and Belle has some money each. If Audrey spends $18 and Belle spends $24 each day, Audrey will have $25 left when Belle has spend all her money. If Audrey spends $13 and Belle spends $30 each day, Audrey will have $139 left when Belle has spend all her money. How much money do they have altogether?

[Ans: 655]

Hi Maths Monster,
Thanks for posting this interesting 4-mark question from Nanyang P6 SA1 2009 paper 2 Q14 and let's look forward for creative solutions from readers in this forum plus our dearest Mathsguru to provide her model solution.
For the reference of readers, this question had been discussed in other forum and blog.

http://psle2010a.blogspot.com/2010/03/14.html
http://www.onsponge.com/forum/35-thinkingmathonsponge/2528-p6-maths.html
http://www.onsponge.com/forum/35-thinkingmathonsponge/1917-p6-maths-2009-nanyang-sa1-paper-2.html

[tisha]

Is it possible to solve these without algebra? These are P5 Questions from past year exam papers for SA1.

I believe algebra is only taught in P6, so just curious how come these questions can be asked for SA1 of P5 :?

Ken and Patrick had $625 at first. After buying some books, the amount of money Ken has left is 4 times the amount of money he spent and the amount of money Patrick has left is 5 times the amount of money he spent. Find the amount of money Patrick had at first if they have a total of $510 left.


There are 85 plates of chicken rice for 80 people. Each adult eats 2 plates of chicken rice and every 3 children share 1 plate of chicken rice. Find the number of adults and children respectively.