Tutor MathsGuru: Ask me for your burning Maths questions!

[tinasen]

Thank you Math Guru.

mathsguru:

tinasen:

Hi MathGuru,
For Q3 \"Millie and Ronnie had a total of $338. After Millie saved $49 and Ronnie spent half of her money,they both had the same amount of money. How much did Millie have at first?\"
As it is stated Millie \"Saved\" $49 I got the following answer which is diffrent from yours. May be I'm wrong.

2*49 = 98
338-98 = 240
240/2 = 120
The final answer I got was 120.

- Tinasen

Hi Tinasen,

Sorry, I've read the question wrongly! Haha...instead of saved $49, I read it as soent $49! Ooopsss...No wonder I thought my answer looks quite weird with fraction in it! Correct answer should be $80.

Here's the amended solution:

http://postimage.org/image/1ssi1dbr8/

Cheers,
MathsGuru

[kwcllf]

Hi,


Please help with the following question.

Peter, Mary and Sam have a total of $1,200. If Peter gave them $25 each, Peter and Mary would have a total amount which was $10 less than Sam. Given that Sam originally had 4 times as much money as Mary, how much did Peter have originally?

Thanks!

[rain29]

Hi,


I need help for the following questions with drawing model.

1) Tom and Jerry had equal amount of money at first. After Tom spent $8 and Jerry spent $32. Tom had 4 times as much as Jerry. How much did Tom have at first?


2) John had $130 and Elicia had $88 at first. After they each spent an equal amount of money. John had 4 times as much money as Elicia. How much money did each of them spend?

Thanks in advance.

[lostbunny]

kwcllf:

Hi,


Please help with the following question.

Peter, Mary and Sam have a total of $1,200. If Peter gave them $25 each, Peter and Mary would have a total amount which was $10 less than Sam. Given that Sam originally had 4 times as much money as Mary, how much did Peter have originally?

Thanks!

Kwcif,

My DH insist I post this answer that he worked out.

P + M -10= S = 1200
595 = 605 ( this is the only combination where the diff is by 10)

S=605-25=580s/4=145M
1200-580S-145M= 475P

Prove
475P-50=425P
145M+25=170M
575PM
580S+25=605S

Maths guru, is this correct?

[autolycus]

kwcllf:

Hi,


Please help with the following question.

Peter, Mary and Sam have a total of $1,200. If Peter gave them $25 each, Peter and Mary would have a total amount which was $10 less than Sam. Given that Sam originally had 4 times as much money as Mary, how much did Peter have originally?

Thanks!

Originally:
Mary has $M
Sam has 4 x $M
Peter has $1,200 - 5 x $M

Then Peter gets generous.

This becomes:
Peter has $1200 - 5 x $M - $25 - $25
Mary has $M + $25
Sam has 4 x $M + $25

But to put it another way...

Sam also has Peter's money + Mary's money + $10
= $1200 - 5 x $M - $50 + $M + $25 + $10
= $1200 - $50 + $25 + $10 - 5 x $M + $M
= $1185 - 4 x $M

So Sam's money can be expressed in 2 ways but must be the same:

4 x $M + $25 = $1185 - 4 x $M
4 x $M + $25 + 4 x $M = $1185
8 x $M = $1185 - $25 = $1160

So $M = $1160/8 = $145

Conclusion:
Mary started with $M = $145
Sam started with 4 x $M = 4 x $145 = $580
Peter had the balance = $1200 - $580 - $145 = $475

After Peter gave them each $25,
Mary had $170
Sam had $605
Peter had $425

[Yu Xuan]

rain29:

Hi,


I need help for the following questions with drawing model.

1) Tom and Jerry had equal amount of money at first. After Tom spent $8 and Jerry spent $32. Tom had 4 times as much as Jerry. How much did Tom have at first?


2) John had $130 and Elicia had $88 at first. After they each spent an equal amount of money. John had 4 times as much money as Elicia. How much money did each of them spend?

Thanks in advance.

Hi

Question 1

Tom --> [ ][ ][ ][ ][$8]
Jery --> [ ][....$32.....]

3 units --> $32 - $8 = $24
1 unit --> $24 / 3 = $8
4 units --> $8 * 4 = $32

$32 + $8 = $ 40

Question 2

Jo --> [Spent][ ][ ][ ][ ]
El --> [Spent][ ]

3 units --> $130 - $88 = $42
1 unit --> $42 / 3 = $14

Using Elicia;
$88 - $14 = $ 74

[Yu Xuan]

kwcllf:

Hi,


Please help with the following question.

Peter, Mary and Sam have a total of $1,200. If Peter gave them $25 each, Peter and Mary would have a total amount which was $10 less than Sam. Given that Sam originally had 4 times as much money as Mary, how much did Peter have originally?

Thanks!

Hi

After transfer;
Sam --> 4 units + $25
Mary --> 1 unit + $25

Since Peter & Mary would have $10 less than Sam, Peter & Mary should have;
4 units + $25 - $10 = 4 units + $15

If Mary has 1 unit + $25, then Peter should have;
4 units + $15 - 1 unit - $25 = 3 units - $10

To find out what Peter started off with, we need to add back the $50 which he transferred to Sam & Mary;
3 units - $10 + $50 = 3 units + $40

Using the $1200 which 3 of them started off with;
4u + 1u + 3u + $40 --> $1200
8u --> $1200 - $40 = $1160
1u --> $1160 / 8 = $145

Peter at first --> 3u + 40 = [ 3*$145 ] + $40 = $475

[rain29]

Hi Yu Xuan,


Thanks for your help.

I can get the answer but my daughter dun understand with my explanation. I will explain to her using your method, hope she can understand better.

[Yu Xuan]

rain29:

Hi Yu Xuan,


Thanks for your help.

I can get the answer but my daughter dun understand with my explanation. I will explain to her using your method, hope she can understand better.

Hi Rain

The pleasure is mine. Nice day.

Yu Xuan

[kwcllf]

Hi All,


Thanks for the great help. I managed to do it using the Model method as my P5 kid can understand better.

Please see below (Sorry, can’t get it into alignment)

M--------[135][10]

S--------[135][10][135][10][135][10][135][10][15][10]
P+M---- [135][10][135][10][135][10][135][10][15]


From the above model (taking into account of S & P+M only):

$1200 – (9 x $10) – (2 x$ 15) = $1080
$1080 ÷ 8 = $135

Therefore originally,
Sam = (4 x $135) + (4 x $10) = $580
Mary = $135 + $10 = $145
Peter = $(1200 – 580 – 145 ) = $475