Tutor MathsGuru: Ask me for your burning Maths questions!

[underthesea]

Hi,


I need help with this P5 maths quesiton.

Leo and Tom are given some money each. If Leo and Tom spend $50 and $25 respectively, Leo still have $600 when Tom has spent all his money. If they spend $25 and $50 each day respectively, Leo will still have $1800 when Tom has spent all his money. How much money is given to Leo.

TIA.

[BigDevil]

underthesea:

Hi,


I need help with this P5 maths quesiton.

Leo and Tom are given some money each. If Leo and Tom spend $50 and $25 respectively, Leo still have $600 when Tom has spent all his money. If they spend $25 and $50 each day respectively, Leo will still have $1800 when Tom has spent all his money. How much money is given to Leo.

TIA.

http://www.postimage.org/image.php?v=PqtKpQJ

[mathsguru]

underthesea:

Leo and Tom are given some money each. If Leo and Tom spend $50 and $25 respectively, Leo still have $600 when Tom has spent all his money. If they spend $25 and $50 each day respectively, Leo will still have $1800 when Tom has spent all his money. How much money is given to Leo.

Hi Underthesea,

My solution is the same as BigDevil. Have added explanation in my working. Hope it helps!

http://www.postimage.org/image.php?v=Ts173bKr

Cheers,
MathsGuru

[underthesea]

Thank you so much for answering my query. DS form teacher can’t solve this problem. She said there’s something wrong with the question!

[Dharma]

mathsguru:

underthesea:

Leo and Tom are given some money each. If Leo and Tom spend $50 and $25 respectively, Leo still have $600 when Tom has spent all his money. If they spend $25 and $50 each day respectively, Leo will still have $1800 when Tom has spent all his money. How much money is given to Leo.

Hi Underthesea,

My solution is the same as BigDevil. Have added explanation in my working. Hope it helps!

http://www.postimage.org/image.php?v=Ts173bKr

Cheers,
MathsGuru

Hi underthesea, BigDevil and mathsguru,

I suspect that there the question is not complete. For this type of question, it should be re-worded as in bold in order for the child not to get confused.

Otherwise, only with the 1st condition, Leo is given $600 + $50 = $650. The number of days for Tom to spend off all his money must be different.

Leo and Tom are given some money each. If Leo and Tom spend $50 and $25 each day respectively, Leo still have $600 when Tom has spent all his money. If they spend $25 and $50 each day respectively, Leo will still have $1800 when Tom has spent all his money. How much money is given to Leo.

Condition 1 (Tom spends all his money in N days)
Leo : 1u - $50N = $600
Tom: 1p - $25N = $0

So; 1p = $25N

Condition 2 (Tom spends all his money in M days)


Leo : 1u - $25M = $1800
Tom: 1p - $50M = $0

So, 1p = $50M

We can equate; $25N = $50M…. N=2M

$600 +$50N = $1800 + $25M
$100M - $25M = $1800 - $600
$75M = $1200
M = 16 days

Amount of money given to Leo = $1800 + $25x16 = $2200

[mathsguru]

underthesea:

Thank you so much for answering my query. DS form teacher can't solve this problem. She said there's something wrong with the question!

Hi Underthesea,

At first, I thought the question was incomplete too (but I thought it was due to typo *no offence ya...*). Haha...like what Dharma said, the 1st scenario should have the 2 words \"each day\". And as stated in my solution, my assumption is that the no. of days is the same for both scenarios. Perhaps, that should be made clear to the students in the question. Otherwise, your DS' form teacher could be right --- the question cannot be solved. :politebleah:

Cheers,
MathsGuru

[BigDevil]

mathsguru:

My solution is the same as BigDevil. Have added explanation in my working. Hope it helps!

:oops: I knew how to work out the answer, but I couldn't quite explain myself.
If we encounter this kind of question in exams, is it sufficient to lay out the answer as I did, or must the students explain their work?

[Andaiz]

BigDevil:

mathsguru:

My solution is the same as BigDevil. Have added explanation in my working. Hope it helps!

:oops: I knew how to work out the answer, but I couldn't quite explain myself.
If we encounter this kind of question in exams, is it sufficient to lay out the answer as I did, or must the students explain their work?

BigDevil, the devil is in the details...the students are told to put down the working and/or models coz in the event that the answer is wrong (copy wrong or just plain careless), the marker can follow the logic and trend of thoughts!

[mathsguru]

BigDevil:

mathsguru:

My solution is the same as BigDevil. Have added explanation in my working. Hope it helps!

:oops: I knew how to work out the answer, but I couldn't quite explain myself.
If we encounter this kind of question in exams, is it sufficient to lay out the answer as I did, or must the students explain their work?

Hi BigDevil,

Don't worry, ur working is good enough to earn u full marks for this question. I added the explanation for Underthesea's reference.

Cheers,
MathsGuru

[quickmind]

KSP:

tamarind:

Thanks in advance. My friend sent me this question :


I am a three digit number. The digit in the tens place is 6 less than the digit in the hundreds place. The tens place is 2 more than the digit in the ones place. If the digit in the ones place is 5, then I am the number ______.

Is this a P1 question?

I think so