Tutor MathsGuru: Ask me for your burning Maths questions!

[MathIzzzFun]

fxchow:

Hi,


Can someone help in this question. TIA

5 friends were playing Wii games on a Friday afternoon from 3 p.m to 6 p.m.
As there were only 4 consoles, they took turns to play.
At any time, 3 of them played while the other 2 friends watched.
If each of them had the same amount of playing time, how many minutes did each child play that afternoon?

Ans: 108 minutes

Hi fxchow,

Total available play time = 3 x 3 h = 9h

So, each will get to play for 9h/5 = 9 x 60 /5 = 108min

cheers.

[MathIzzzFun]

SoWoW:

Help needed for the following questions:


Q1 : Tom and Jerry each has some money. If Tom spends $90 per day and jerry spends $45 per day, Tom will have $1100 left when Jerry has spent all his money. If Tom spends $45 each day and Jerry spends $90 each day. Tom will have $1700 left when Jerry has spent all his money. How much did Jerry have?

Q2 : Ravi had a total of 204 goldfish and swordtails in the ratio of 9:8. After she gave away an equal number of each type of fish , the number of goldfish and swordtails left was in the ratio of 9:5 respectively. What was the total number of fish that she had given away?


Q3: Aifang, Bala and Cindy shared some sweets. Aifang received 1/11 of the sweets. Bala received 1/4 of the number of sweets Cindy received. When cindy gave away 104 sweets to be shared between Aifang and Bala, they found that all of them had the same number of sweets. How many sweets were there at first?

Hi

Hope this helps :lol:

Q1 - http://www.flickr.com/photos/62167097@N02/5704049418/in/photostream

Q2 - http://www.flickr.com/photos/62167097@N02/5703483755/in/photostream

Q3 - http://www.flickr.com/photos/62167097@N02/5702496453/in/photostream

cheers.

[fxchow]

MathIzzzFun:

fxchow:

Hi,


Can someone help in this question. TIA

5 friends were playing Wii games on a Friday afternoon from 3 p.m to 6 p.m.
As there were only 4 consoles, they took turns to play.
At any time, 3 of them played while the other 2 friends watched.
If each of them had the same amount of playing time, how many minutes did each child play that afternoon?

Ans: 108 minutes

Hi fxchow,

Total available play time = 3 x 3 h = 9h

So, each will get to play for 9h/5 = 9 x 60 /5 = 108min

cheers.

Hi MathIzzzFun,

Thank you very much

[Superbugs]

Hi there, appreciate it that someone can assist me on the following questions:


Q1) There are 8 stacks of chairs and 12 chairs in each stack. Each chair is equally spaced apart to form the perimeter of a rectangle. If the no. of chairs placed along its length is thrice the no. of chairs placed along its breadth, how many chairs are placed equally along one of the length of the rectangle.

12x9 = 108
108-4 (4 corners) = 104
108/8 = 13
13x3=39
39+2 (2 corners) = 41

But the answer is 42 and instead of minusing the 4 corners, they add the 4 corners
108+4=112
112/8=42
Why is that so?

Q2) J bought some strawberries and wanted to put them in boxes. If she put 4 strawberries into each box, there would be 3 strawberries left. If she put 6 strawberries into eah box, she would have 5 strawberries left.

If the no. of strawberries was between 100 and 150, how many strawberries did J buy?

I used the common multiple method but got many answers:

Common Multiple of 4, starting with 100 plus 3 excess:
103, 107, 111, 114, 119, 123, 127, 131, 135 etc

Common Multiple of 6, starting with 102 plus 5 excess:
107, 113, 119, 125, 131, 137

Why the answer is not 107 or 119 but 131? If this is not the correct method to apply, any other method?

[Superbugs]

Hi there, someone pls help me with the following questions:


Mdm Lek had 57 apples and oranges altogether. There were 3 fewer oranges than apples. Sh egave away half as many oranges as apples and was left with twice as many oranges as apples. How many apples did she give away?

I can only do up to here:
2U+3 => 57
1U=>27
Oranges =>27
Apples => 27+3 => 30

[Superbugs]

Pls help with this question too with other method other than guess and check:


Farmer Tan has ducsk and cows on his farm. The total number of ducks and cows is between 20 and 40. The ratio of the total no. of duck’s legs to the total no. of cow’s legs is 5:9. What is the total no. of ducks and cows on the farm?

Duck=> 2 legs
Cow=> 4 legs
Ratio of duck’s legs to cow’s leg
5:9
Since cow has 4 legs, I multiply the duck ratio by 2 to be on par with the cow legs, I get 10:9 => 19
Then guess and check method:
20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40
Since only 38 can be divisible by 19, the ans is 38.
Is this method correct?

Any other method?

[Dharma]

Total No. of Ducks = D

Total No. of Cows = C
Total no. of legs = 2D + 4C

Ratio of the no. of legs of ducks : no. of legs of cows = 2D : 4C = 5 : 9
18D = 20C
D : C = 20 : 18

Total no. of ducks and cows = 20 + 18 = 38

[MathIzzzFun]

Superbugs:

Hi there, someone pls help me with the following questions:


Mdm Lek had 57 apples and oranges altogether. There were 3 fewer oranges than apples. Sh egave away half as many oranges as apples and was left with twice as many oranges as apples. How many apples did she give away?

I can only do up to here:
2U+3 => 57
1U=>27
Oranges =>27
Apples => 27+3 => 30

Hi

Hope this helps :lol:

http://www.flickr.com/photos/62167097@N02/5705956596/in/photostream

cheers.

[bleeze]

Hi, someone pls help me with the following question:


There were 1260 boys and girls in an amusement park. When 5/8 of the girls and 7/13 of the boys left the amusement park, the number of boys and the number of girls remaining in the park is the same. How many more girls than boys were there in the amusement park at first?

Ans: 140

Thanks

[Superbugs]

Dharma:

Total No. of Ducks = D

Total No. of Cows = C
Total no. of legs = 2D + 4C

Ratio of the no. of legs of ducks : no. of legs of cows = 2D : 4C = 5 : 9
18D = 20C
D : C = 20 : 18

Total no. of ducks and cows = 20 + 18 = 38

How did you derive at 18D:20C? You mean cross multiply 2D with 9 and 4C with 5? If yes, why?