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akulion
03-10-2006, 12:59 AM
:salamalaikum:

Here it is - the ultimate test of your mathematics skills!!! :hiding:

How it works

- I will post a maths question daily

- Members will try and solve it giving their working and answers

- I will post the answer the next day OR someone gets the correct answer & working OR after 4 people have tried to work the question (whichever comes first), if I am offline, then the new question will be posted the next day.

- There are no 'rewards' or 'prizes' but its just for fun and learning some maths along the way too :D

Rules:

1 - Use of calculators is strictly prohibited! (you can cheat and use one, but remember if you cant be fair even alone then how can you expect to be fair to others?)

2 - ALL working MUST be shown, this is not just about getting the right answer, but its also to see if the person knows how to work the problem and most importantly others can learn how to solve problems using the examples of solved questions.

================================================== ===========

So here is the first Question: (a simple one to start hehe :D )

Q1)
A train passes an average of 3 stations every 10 minutes.
At this rate, how many stations will it pass in one hour?

Protected_Diamond
03-10-2006, 01:01 AM
:sl: warhmatulahi wabarakathu

:uhwhat I got no maths skills....

Im awful at maths.

:w: warhmatulahi wabarakathu

akulion
03-10-2006, 01:04 AM
You have to show your working sis....this way we can all learn to solve maths problems along the way....

Guesses cant be allowed since no one really gets to see how the person got to their answer...

An example of working:

Q: What is twice of 4 ?

Working:

Twice of 4 is: 4 x 2 = 8

Protected_Diamond
03-10-2006, 01:25 AM
:sl: warhmatulahi wabarakathu

Sorry Akhee, i skipped rule no. 2 out. Okay here goes;

A train passes an average of 3 stations every 10 minutes.
At this rate, how many stations will it pass in one hour?

1 hour = 60 mins.

10 mins. X 3 = 3 stations

60 mins. X 3 = 18 stations :)

:w: warhmatulahi wabarakathu

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akulion
03-10-2006, 01:34 AM
Yaaa :D good work sis

Complete working of the Question is:

1 hour has 60 minutes

And if the train passes 3 stations every 10 minutes

Therefore : 3 x (60/10) = 18

============================================

Next Question:

Q2
During a certan week, a post office sold \$280 worth of 14-cent stamps.
How many of these stamps did they sell?

Protected_Diamond
03-10-2006, 01:38 AM
:sl: warhmatulahi wabarakathu

Phew!! I thought i was going to embarass myself by getting it wrong. ;D

I'll leave Q2 to someone who's good at maths insha Allah.

:w: warhmatulahi wabarakathu

akulion
03-10-2006, 12:58 PM
Next Question still stands:

Q2
During a certan week, a post office sold \$280 worth of 14-cent stamps.
How many of these stamps did they sell?

akulion
03-10-2006, 02:03 PM
Beautifully done bro!!
Masha'Allah :D

Solution:

\$1 contains 100 cents
Thus \$280 contain: 280 x 100 = 28000
Number of stamps sold: 28000 / 14 = 2000

-----------------------------------------------------------------

Q3
[ 90 - 8( 20/4 ) ] / 1/2
<----(thats 1 over 2)

life
03-10-2006, 02:21 PM
[90-8(20/4)]/1/2

[90-(8*20/4]/1/2
[90-(160/4]/1/2
[90-40]/1/2
50/1/2
50*2/1
=200

is it correct :?

aakhirah
03-10-2006, 02:22 PM
[ 90 - 8( 20/4 ) ] / 1/2

= [ 90 - 8( 20/4 ) ] x 2 // dividing by half is the same as multiplying by 2

= [ 90 - 8( 5 ) ] x 2 // 20 divide by 4 = 5

= [ 90 - 40 ] x 2 // 8( 5 ) = 8 x 5 = 40

= [ 50 ] x 2 // 90 - 40 = 50

= 100 // 50 x 2 = 100

akulion
03-10-2006, 02:37 PM
Bro aakhira got it corect masha'Allah :D

Solution:
[ 90 - 8( 20/4 ) ] / 1/2

= [ 90 - 8(5) ] / 1/2

= [ 90 - (40) ] / 1/2

= [ 50 ] / 1/2

When a number is divided by a fraction, we multiply that number with the reciprocal of that fraction (e.g. reciprocal of 1/2 is 2/1)

= [ 50 ] x 2

Other examples of reciprocals are:
Reciprocal of 2/3 is 3/2
Reciprocal of 5 is 1/5

Please note that the above question could only have been solved following the law of BODMAS = Brackets, Off, Division, Multiplication, Addition, Substraction)
If we try and solve it another way the answer would be wrong.

Now one final Question for the day...then I have to run to my classes lol

Q4
In a certain pet store there are 24 hampsters and 9 cats.
What is the ratio of cats to hampsters at this store?

life
03-10-2006, 02:39 PM
format_quote Originally Posted by aakhirah
[ 90 - 8( 20/4 ) ] / 1/2

= [ 90 - 8( 20/4 ) ] x 2 // dividing by half is the same as multiplying by 2
you sure :rollseyes

2/1 is equal to 2

but ½ is not

aakhirah
03-10-2006, 02:41 PM
format_quote Originally Posted by akulion
b]Q4
In a certain pet store there are 24 hampsters and 9 cats.
What is the ratio of cats to hampsters at this store?
[/b]
Greatest common factor = 3.

24/3 = 8
9/3 = 3

Therefore, ratio of cats to hamsters is 3:8.

aamirsaab
03-10-2006, 02:44 PM
:sl:
format_quote Originally Posted by akulion
Q4
In a certain pet store there are 24 hampsters and 9 cats.
What is the ratio of cats to hampsters at this store?

Here cometh the pain..eth

cats to hampsters: 9:24
Can be reduced to 3:8 (divide both 9 and 24 by 3)
therefore, the ratio is 3 cats to 8 hampsters - for every 3 cats there are 8 hampsters.

akulion
03-10-2006, 02:51 PM
Yup masha'allah all those who got the answer 3/8 or 3 : 8 got it correct :D

Solution:

Question asks for: Ratio of Cats : Hampsters

Cats: 9
Hampsters 24

A ratio can be represented in Two ways:

Cats : Hampsters

OR

Cats / Hampsters

Thus the ratio is 9 : 24 OR 9/24

Which can be reduced to

3 : 8 OR 3/8

-------------------------------------------
Ok i know I said I was leaving but masha'Allah everyone is so quick with replies here I was caught as I was leaving :p but this is the last question for the day and then I go :D

Q5
In a class the ratio of boys to girls is 5 to 3
If there is a total of 32 students in the class then how many are boy and how many are girls?

aakhirah
03-10-2006, 03:03 PM
format_quote Originally Posted by akulion
Q5
In a class the ratio of boys to girls is 5 to 3
If there is a total of 32 students in the class then how many are boy and how many are girls?
5 + 3 = 8

32 / 8 = 4

Therefore, number of boys = 5 x 4 = 20.
and number of girls = 3 x 4 = 12.

akulion
03-10-2006, 07:41 PM
wow masha'allah bro ur a true maths wizard :D

Ok a new question....(a lil tougher one)

Q6
A class of 40 students is to be divided into smaller groups.
If each group is to contain 3, 4 or 5 people, what is the largest number of groups possible leaving no one out?

aamirsaab
03-10-2006, 08:11 PM
:sl:
format_quote Originally Posted by akulion
Q6
A class of 40 students is to be divided into smaller groups.
If each group is to contain 3, 4 or 5 people, what is the largest number of groups possible leaving no one out?

3 goes into 40 twelve times, well actually thirteen but...
..plus one group of 4 will give you 10 groups: 12 groups of 3 = 36 plus one group of 4 = 40.

If we did 3 times by thirteen we would have 39 students and one guy left out - since groups can only be made out of 3, 4 or 5 students, we cannot use this method.

By using a group of 5, this would reduce the total amount of groups - the question asks for the largest, hence the method I explained is justified.

Mainul_Islam
03-11-2006, 02:28 AM
hey! stop hogging all the fun!

nice thinking bro aamirsaab, i didnt think of 12 groups of 3 + 1 group of 4 = 40

akulion
03-11-2006, 07:20 AM
masha'Allah bro aamirsaab excellent!
That was a trick question and you got it :D

Ok now another Question....simple one :D

Q7
An office has 27 employees. If there are 7 more women then there are men in the office, How many employees are women?

Eric H
03-11-2006, 03:21 PM
Greetings to you maths wizard

27-7 =20
20/2 =10
10+7=17 women; and if you are doing algebra you will be able to work out that there will be no peace for the minority of men working there.;D

and here is one for you if you are not too busy studying;

A farmer dies and leaves his sheep to be divided between his two sons, the sons don’t want the sheep and sell them.

However many sheep there are in the flock is the same as, how much money they got for each sheep.

The big brother divides the money and ends up with one more ten pound note than his little brother, so he gives his brother the pound coins from the sale.

The little brother said that is not fair you have more than me, so big brother makes a cheque out for the difference, so how much is the cheque for?

Eric

The Ruler
03-11-2006, 06:31 PM
arrrgh maths!!! v enuf of it in skool already :grumbling

neways i dont get da question Eric H :? :rollseyes

:w:

------
03-11-2006, 06:36 PM
Argh!!!! :heated: Maths in skool and on the in the forum! Stop killing us!!!:rant: :grumbling

akulion
03-11-2006, 07:07 PM
no peace for the men in the office..so true lol

A farmer dies and leaves his sheep to be divided between his two sons, the sons don’t want the sheep and sell them.

However many sheep there are in the flock is the same as, how much money they got for each sheep.

The big brother divides the money and ends up with one more ten pound note than his little brother, so he gives his brother the pound coins from the sale.

The little brother said that is not fair you have more than me, so big brother makes a cheque out for the difference, so how much is the cheque for?
Lol man this dosent seem like a maths problem to me at all :p

10 sheep
10 pounds per sheep
Thus 10 x 10 = 100 pounds

100/2 = 50 pounds each

Now if the brother had 10 more pounds that his little brother he would have 60
so the check for the difference would be 10 pounds

However you also said "so he gives his brother the pound coins from the sale."
Assuming that instead of a 10 pound note he gave his prother 10 pound coins
Then in that case the cheque would be of 0 pounds since they would have equal money already.

Is that correct?

Eric H
03-11-2006, 09:53 PM
Greetings and peace
100/2 = 50 pounds each
If you think logically a hundred pounds is ten X ten pound notes, so they would both have exactly the same £50 each, and the big brother would not have to write a cheque for the difference.

If it helps you have come up with the wrong number of sheep; this is not a trick question, but it requires you to do a bit more thinking.

I don't think you should spend too much time on this if you have your exams shortly, maybe I should give you a clue to put you out of your misery.

the number you are looking for must give you an odd number of ten pound notes when multiplied together, and you do not have to think of a big number/
This dosent seem like a maths problem
There are only four things you can do in maths, add, subtract, divide and multiply; the sheep problem needs you to do three of those things to solve it so it must be maths.

There must be better things to do to pass the time;;D :rant: :heated:
Eric

akulion
03-12-2006, 02:29 AM
3 Sheep
Each sold for 10 pounds.
Total 30 Pounds.
Big bro gets 20 pounds
Lil bro gets 10 pounds
Big bro gives lil bro 5 pound cheque.

But what dosent make any sence is this statement "so he gives his brother the pound coins from the sale"

Does that imply that he gives his brother 5 pounds in coins?
Because if so then no Cheque is necessary.
If not then the Cheque would be 5 Pounds

Furthermore what the question does not specify is if the money was divided equally or not "The big brother divides the money and ends up with one more ten pound note than his little brother"
So for all we know the money was divided unevenly.

The reason I am trying not to assume anything is because the exam I am about to give (GMATS) warns heavily against assumptions.
There is a question format on it called "data sufficiency" which tests a person ability to be able to judge if the question is solvable based on the given data or not.

Eric H
03-12-2006, 08:02 AM
Greetings akulion,

I will be kind to you because you really should be spending time studying.
akulion
Furthermore what the question does not specify is if the money was divided equally or not "The big brother divides the money and ends up with one more ten pound note than his little brother"
If you looked a little closer at the last part of the question,
Eric
The little brother said that is not fair you have more than me, so big brother makes a cheque out for the difference, so how much is the cheque for?
The little brother wants the money shared out fairly, so would it be safe to assume that he wants the same as big brother?

You need to find a number when multiplied by itself gives you an odd number of tens.

6x6=36

big brother takes two ten pound notes =£20
little brother takes ten pound plus the six pound coins =£16

you might be tempted to say the cheque is for £4, but in fact it is for half that so they both end up with £18,

The problem was solvable as it was, but it requires you to do a lot of thinking, once you worked out the numbers the calculations were very simple.

If you multiply numbers by themselves you might find that the ones giving an odd number of tens end in six.

It must have been some strange and weird person thinking up this little test originally.

I am off to church followed by a twenty hour shift at work, so no more questions for a while

I pray that you will gain from your exams, take care

Eric

akulion
03-13-2006, 04:24 AM
man that wasnt a maths problem :p lol

but anyways nice one....

moving on to another question now....

Q8
If 1 Tic equals 3 Tacs
And 2 Tacs equal 5 Tocs
Then what is the ratio of 1 Tic to 1 Toc?

Mainul_Islam
03-13-2006, 04:59 AM
Q8
If 1 Tic equals 3 Tacs
And 2 Tacs equal 5 Tocs
Then what is the ratio of 1 Tic to 1 Toc?

----------

5 Tocs / 2 Tacs = 2.5.

1 Tac = 2.5 Tocs.

1 Tic = 3 Tacs (2.5 Tocs x 3).

2.5 Tocs x 3 = 7.5 Tocs.

1 Tic = 7.5 Tocs.

or a simpler way:

1 Tic = (3 Tacs / 2 Tacs) x 5 Tocs

1 Tic = 1.5 Tacs x 5 Tocs

1 Tic = 7.5 Tocs