Tutor MathsGuru: Ask me for your burning Maths questions!

[Vanilla Cake]

Hifive:

1) A class was fixing a puzzle of their photos. In the first hour, the ratio of the number of fixed pieces to unfixed pieces is 1:5. In the next hour, they fixed another 15 pieces of the puzzle. Finally, the number of fixed pieces became 60% of the unfixed pieces. How many pieces were there in the puzzle?

This question is from Catholic High School (Primary) 2009 P5 SA2 Paper 2 Q10 [3 marks]

DD2's workings
Before
F : UF
1 : 5
4 : 20

After
F : UF
3 : 5
9 : 15

5u=15
24u=72

Number of pieces in the puzzle was 72

VC's mum

[Brenda10]

Hifive:

Hi everyone


Need help on the following questions:

1) A class was fixing a puzzle of their photos. In the first hour, the ratio of the number of fixed pieces to unfixed pieces is 1:5. In the next hour, they fixed another 15 pieces of the puzzle. Finally, the number of fixed pieces became 60% of the unfixed pieces. How many pieces were there in the puzzle?


Source : Catholic High SA2 2009 P5

Thanks in advance.

Working:
60/100 = 3/5


At First
Fixed unfixed
1 5
x8 x8
8 40

At End
Fixed Unfixed
3 5
x6 x6
18 30

18 - 8 = 10 units and 40 - 30 = 10 units


10 units = 15
1 unit = 1.5
48 units = 48 x 1.5 = 72

Thank you.

[corvette]

Mrs Gopal and Mrs Ari went to the supermarket. Both women decided to spend all their money on either apples or pears and they would not buy the same fruit.

If Mrs Gopal bought only pears, she would have 9 more fruit than Mrs Ari.
If she bought only apples, she would have 41 more fruit than Mrs Ari.
How much more money has Mrs Gopal than Mrs Ari? Each apple cost 40 cents and each pear cost 60 cents.

Anyone can better explain this question without using algebra? Thank you very much. :?:

[elkniwt]

Hi Herbie,


This question is interesting as the ans requires not only up to minutes, but seconds as well. Here's the working :

At 11am, Sharon has travelled 2 x 80 = 160 km
To travel 160 km, Kim takes 160/90 hr = 1 hr 46 min 40 secs
a) Using timeline to work backwards from 11am, Kim set off at 9:13:20

Remaining distance after 11am = 240 - 160 = 80km
Sharon takes 80/80 hr = 1 hr
Kim takes 80/90 hr = 8/9 hr
1- 8/9 = 1/9 hr = 6 min 40 sec
Sharon arrived 6 min 40 sec later.

Regards.

Herbie:

Hi I have one qn

Town A and Town B were 240km apart. Sharon left Town A for Town B at 9am travelling at an average speed of 80km/h. Kim left Town A sometime later than Sharon and overtook her at 11am. Kim's travelling speed was 90km/h

a. at what time did kim leave town A.

b. How much later did sharon arrive in Town B than Kim?

Tx

[Brenda10]

corvette:

Mrs Gopal and Mrs Ari went to the supermarket. Both women decided to spend all their money on either apples or pears and they would not buy the same fruit.

If Mrs Gopal bought only pears, she would have 9 more fruit than Mrs Ari.
If she bought only apples, she would have 41 more fruit than Mrs Ari.
How much more money has Mrs Gopal than Mrs Ari? Each apple cost 40 cents and each pear cost 60 cents.

Anyone can better explain this question without using algebra? Thank you very much. :?:

Hi, this question looks very familiar. Do you get it from Maths Test Primary 5 CA2 or pass year paper?Thank you

[Vanilla Cake]

Brenda10:

corvette:

Mrs Gopal and Mrs Ari went to the supermarket. Both women decided to spend all their money on either apples or pears and they would not buy the same fruit.

If Mrs Gopal bought only pears, she would have 9 more fruit than Mrs Ari.
If she bought only apples, she would have 41 more fruit than Mrs Ari.
How much more money has Mrs Gopal than Mrs Ari? Each apple cost 40 cents and each pear cost 60 cents.http://www.onsponge.com/forum/35-thinkingmathonsponge/4918-2010-maha-bodhi-prelim-q6.html
Anyone can better explain this question without using algebra? Thank you very much. :?:

Hi, this question looks very familiar. Do you get it from Maths Test Primary 5 CA2 or pass year paper?Thank you

It's from Maha Bodhi 2010 P6 Prelim Paper 2 Q6 [3 marks] first posted by http://www.kiasuparents.com/kiasu/forum/viewtopic.php?t=280&postdays=0&postorder=asc&start=1770 on 14 Sep 2010 17:07

VC's mum

[Brenda10]

Vanilla Cake:

Brenda10:

[quote=\"corvette\"]Mrs Gopal and Mrs Ari went to the supermarket. Both women decided to spend all their money on either apples or pears and they would not buy the same fruit.

If Mrs Gopal bought only pears, she would have 9 more fruit than Mrs Ari.
If she bought only apples, she would have 41 more fruit than Mrs Ari.
How much more money has Mrs Gopal than Mrs Ari? Each apple cost 40 cents and each pear cost 60 cents.http://www.onsponge.com/forum/35-thinkingmathonsponge/4918-2010-maha-bodhi-prelim-q6.html
Anyone can better explain this question without using algebra? Thank you very much. :?:

Hi, this question looks very familiar. Do you get it from Maths Test Primary 5 CA2 or pass year paper?Thank you

It's from Maha Bodhi 2010 P6 Prelim Paper 2 Q6 [3 marks] first posted by http://www.kiasuparents.com/kiasu/forum/viewtopic.php?t=280&postdays=0&postorder=asc&start=1770 on 14 Sep 2010 17:07

VC's mum[/quote]Hi VC's mum

Thank you.

You're really very resourceful.

[YLH88]

[quote]When both Machines P and Q are used, a book can be printed in 5 hours. When printing a book, Machine P broke down. As a result, it took 7 hours to complete the printing of the book. If it would take Machine Q 8 hours 20 minutes to print the book alone, (a) how long was Machine P used before it broke down? (b) how long would it take to print the book using only Machine P? [4 marks][Answer given: 2 hours before, 12½ h]



Q : 8 1/3 h --> 1 book
7 h --> 7 x 3/25 = 21/25 book
5 h --> 5 x 3/25 = 3/5 book

1 - 21/25 = 4/25 book

1 - 3/5 = 2/5 book

P : 2/5 book --> 5 h
4/25 book --> 4/25 x 5/2 x 5 = 2 h
1 book --> 5/2 x 5 = 12 1/2 h

a) It was 2 h.

b) It was 12 1/2 h[/quote]Hi all,

The above question is from Maha Bodhi 2010 P6 Prelim Paper 2 Qn 11, solution was posted in this link http://psle2010a.blogspot.com/2010/09/maha-bodhi-p6-prelim-2010-paper-2q11.html

but I don't understand the step 1 - 3/5 = 2/5 book, can someone please help ?? :?

Thank you.

[Tang]

YLH88:

[quote]When both Machines P and Q are used, a book can be printed in 5 hours. When printing a book, Machine P broke down. As a result, it took 7 hours to complete the printing of the book. If it would take Machine Q 8 hours 20 minutes to print the book alone, (a) how long was Machine P used before it broke down? (b) how long would it take to print the book using only Machine P? [4 marks][Answer given: 2 hours before, 12½ h]



Q : 8 1/3 h --> 1 book
7 h --> 7 x 3/25 = 21/25 book
5 h --> 5 x 3/25 = 3/5 book

1 - 21/25 = 4/25 book

1 - 3/5 = 2/5 book

P : 2/5 book --> 5 h
4/25 book --> 4/25 x 5/2 x 5 = 2 h
1 book --> 5/2 x 5 = 12 1/2 h

a) It was 2 h.

b) It was 12 1/2 h

Hi all,

The above question is from Maha Bodhi 2010 P6 Prelim Paper 2 Qn 11, solution was posted in this link http://psle2010a.blogspot.com/2010/09/maha-bodhi-p6-prelim-2010-paper-2q11.html

but I don't understand the step 1 - 3/5 = 2/5 book, can someone please help ?? :?

When both Machines P and Q are used, a book can be printed in 5 hours.



Thank you.[/quote]
Hi,

See underlined.

[atutor2001]

YLH88:

Q : 8 1/3 h --> 1 book
7 h --> 7 x 3/25 = 21/25 book
5 h --> 5 x 3/25 = 3/5 book

1 - 21/25 = 4/25 book

1 - 3/5 = 2/5 book

P : 2/5 book --> 5 h
4/25 book --> 4/25 x 5/2 x 5 = 2 h
1 book --> 5/2 x 5 = 12 1/2 h

a) It was 2 h.

b) It was 12 1/2 h

Hi all,

The above question is from Maha Bodhi 2010 P6 Prelim Paper 2 Qn 11, solution was posted in this link http://psle2010a.blogspot.com/2010/09/maha-bodhi-p6-prelim-2010-paper-2q11.html

but I don't understand the step 1 - 3/5 = 2/5 book, can someone please help ?? :?

Thank you.

Hi,
I find the solution not suitable for P6. Anyway, the reasoning is as follows :

Under normal situation
Fraction of book printed by machine Q = 3/5 of the book (in 5 hours)
so the remaining fraction must be printed by machine P : 1 - 3/5=2/5 of the book (also in 5hrs)

This gives the relationship that P can print 2/5 of the book in 5 hours.

So with the \"breakdown\" Q has printed a total of 21/25 of the book. The remaining 4/25 of the book must have been printed by P before it broke down.... we can find the time P has been printing before it breaks down.