Tutor MathsGuru: Ask me for your burning Maths questions!

[MathIzzzFun]

wahwah:

Hi MathIzzzFun,


Thanks so much for the explanation. My boy wants to thank you too!

u r welcome

cheers.

[andante]

MathIzzzFun:

andante:

Sorry to bother again
I don't really understand why 2 x 64 km since Mr Koh travel 64km in the first part ... does it mean XY=64 ??? why ??

Thx

Hi

eg. if for every 200m, jenny walked 50m, then for every 400m, she would have walked 2 x 50m = 100m since 200m = 2 x 100m; assuming she walked at constant pace.

similarly, for a distance XY, Mr Koh travelled 64km
so for a distance of 2 x XY, he would have travelled 2 x 64 km, for 3 x XY, he would have travelled 3 x 64 km and so forth.

suppose Mr Koh's speed was S1 and Mr Tan's speed was S2, we can divided XY into (S1+S2) parts so that at meeting point A, Mr Koh would have travelled S1 part (=64km) and Mr Tan would have travelled S2 parts.

Now, when the distance is 2 x XY then total number of parts will now be 2 x (S1+S2), and Mr Koh would have travelled 2 x S1 parts = 2 x 64km

cheers.

My girl can understand it now. We really appreciate your help very much.
Thank you very much !!!

[MathIzzzFun]

andante:

MathIzzzFun:

[quote=\"andante\"]
Sorry to bother again
I don't really understand why 2 x 64 km since Mr Koh travel 64km in the first part ... does it mean XY=64 ??? why ??

Thx

Hi

eg. if for every 200m, jenny walked 50m, then for every 400m, she would have walked 2 x 50m = 100m since 200m = 2 x 100m; assuming she walked at constant pace.

similarly, for a distance XY, Mr Koh travelled 64km
so for a distance of 2 x XY, he would have travelled 2 x 64 km, for 3 x XY, he would have travelled 3 x 64 km and so forth.

suppose Mr Koh's speed was S1 and Mr Tan's speed was S2, we can divided XY into (S1+S2) parts so that at meeting point A, Mr Koh would have travelled S1 part (=64km) and Mr Tan would have travelled S2 parts.

Now, when the distance is 2 x XY then total number of parts will now be 2 x (S1+S2), and Mr Koh would have travelled 2 x S1 parts = 2 x 64km

cheers.

My girl can understand it now. We really appreciate your help very much.
Thank you very much !!![/quote]u r welcome.

cheers.

[she0407]

wahwah:

Hi MathIzzzFun,


Thanks so much for the explanation. My boy wants to thank you too!

Me too. Thanks for the clear explanation.

[kwcllf]

Hi,


Please help with the following question:

When Michelle was 25 years old, Adrian’s age was twice that of Nan. At present, Nan is 10 years old and Michelle is twice the age of Adrian. What is the age of Nan when Michelle is 40 years old?

Thanks!

[2DMommy]

Nee help with this ratio question.


The ratio of $2 notes and $10 notes in Pei Ling’s wallet was 5:4. Pei Ling exchanged 15 pieces of her $10 notes for $2 notes. After which, she had 20 times as many $2 notes as $10 notes. What was the total value of the $2 notes and $10 notes in Pei Ling’s wallet in the end?

Thank you in advance.

[MathIzzzFun]

2DMommy:

Nee help with this ratio question.


The ratio of $2 notes and $10 notes in Pei Ling's wallet was 5:4. Pei Ling exchanged 15 pieces of her $10 notes for $2 notes. After which, she had 20 times as many $2 notes as $10 notes. What was the total value of the $2 notes and $10 notes in Pei Ling's wallet in the end?

Thank you in advance.

Hi

at first:
number of $2 notes : $10 notes = 5:4
value of $2 notes : $10 notes = 5 x 1 : 4 x 5 = 5 : 20 = 5u : 20u

in the end:
number of $2 notes : $10 notes = 20 : 1
value of $2 notes : $10 notes = 20 x 1 : 1 x 5 = 20 : 50 = 20u : 5u

so 20u - 5u = 15u = $10 x 15 = $ 150
1u = $10

in the end,
value of $2 notes = 20u = 20 x $10 = $200
value of $10 notes = 5u = 5 x $10 = $50

cheers.

[MathIzzzFun]

kwcllf:

Hi,


Please help with the following question:

When Michelle was 25 years old, Adrian's age was twice that of Nan. At present, Nan is 10 years old and Michelle is twice the age of Adrian. What is the age of Nan when Michelle is 40 years old?

Thanks!

Hi

when Michelles was 25yo,
Nan = [u]
Adrian= [u][u]

Now,
Nan = [10]
Adrian =[10][u] --- age difference remains the same
Michelle = [10][u][10[u]

so, when Michelle was 25yo,
Michelle = Adrian's age + [10][u] --- age difference remains the same
25 = [u][u][u][10]
[u]=5

Michelle's age now = 20+2[u] = 30
so when Michelle is 40 yo, Nan's age = 10 +40-30=20 years old.

cheers.

[kwcllf]

Thanks Bluebelt! :salute:


Really appreciate all your help.

[2DMommy]

Need help with these two questions


1)If Gary gives Hillary $50, both of them will have the same amount of money. If Hillary gives Gary $22, the ratio of Gary’s money to Hillary’s money will become 2:1. How much money does Hillary have?

2)Ben, Rachel and Willy had 8.61 kg of modeling clay altogether. Ben gave Rachel 0.54kg of clay, Rachel gave Willy 0.21 clay and Willy gave Ben 0.37kg of clay. Ben then had twice as much clay as Rachel and Rachel had twice as much clay as Willy. How much clay did Willy have at first?

Thank you so much !