## Q&A - P5 Math

### Re: Q&A - P5 Math

MathIzzzFun wrote:
Trina wrote:Please assist with this question:

There are 40 pupils in a class. Each boy donated \$3 and each girl donated \$2. The boys donated \$30 more than the girls.
How many boys are there?
How many girls are there?

Thanks!

Assume all boys donated, total amount --> 40 x \$3 = \$120
\$120 - \$30 = \$90 --- excess amount to be reduced by girls' donation
Number of girls = \$90/(\$3+\$2) = 18
Number of boys = 40-18 = 22

cheers.

Thanks but still dont get it.. Can provide narration? Thanks

Trina
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### Re: Q&A - P5 Math

Luke had \$140 and Issac had \$92 at first. After they spent an equal amount of money, Luke had 4 times as much money as Isaac. How much did each of them spend?
(not sure if this has been asked before, pls refer me to correct page. Thanks!)

ttyh
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### Re: Q&A - P5 Math

ttyh wrote:Luke had \$140 and Issac had \$92 at first. After they spent an equal amount of money, Luke had 4 times as much money as Isaac. How much did each of them spend?
(not sure if this has been asked before, pls refer me to correct page. Thanks!)

3 units -> \$140 - \$92 = \$48
1 unit -> \$48 / 3 = \$16

\$92 - \$16 = \$76

Each of them spent \$76

php
KiasuGrandMaster

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### Re: P5 Onsponge Conquer Problem Sums Answer key

If you need the whole answer key, I don't think I could help. But if you just need some answers from the answer key, then you can go to the website. http://www.onsponge.com/shop/online-solutions.html
Hope I helped

Trevortan
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### Re: Q&A - P5 Math

Serene, Fabian and Eileen shared their prize money of \$4100 among themselves. Twice of Serene's share was equal to 5 times of Fabian's share. 4 times of Serene's share was also equal to 3 times of Eileen's share. Calculate Serene's share.

Help ...... please. How should the answers be presented and is this really a P5 appropriate question?

Thank you very much.

Oracle
OrangeBelt

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### Re: Q&A - P5 Math

Oracle wrote:Serene, Fabian and Eileen shared their prize money of \$4100 among themselves. Twice of Serene's share was equal to 5 times of Fabian's share. 4 times of Serene's share was also equal to 3 times of Eileen's share. Calculate Serene's share.

Help ...... please. How should the answers be presented and is this really a P5 appropriate question?

Thank you very much.

Hi Oracle,

One Possible Solution:

Twice of Serene's share was equal to 5 times of Fabian's share.
This means that ratio of Serene's share to Fabian's share is 5:2
(Just interchange the 2 numbers)

4 times of Serene's share was also equal to 3 times of Eileen's share.
This means that ratio of Serene's share to Eileen's share is 3:4
(Just interchange the 2 numbers)

Ratio of Serene's share to Fabian's share is 5:2
Ratio of Serene's share to Eileen's share is 3:4

Ratio of Serene's share to Fabian's share to Eileen's share is 15:6:20

15 + 6 + 20 = 41 units
41 units = \$4100

Can you work from here?

Cheers

speedmaths.com

.

speedmaths.com
KiasuGrandMaster

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### Re: Q&A - P5 Math

Oracle wrote:Serene, Fabian and Eileen shared their prize money of \$4100 among themselves. Twice of Serene's share was equal to 5 times of Fabian's share. 4 times of Serene's share was also equal to 3 times of Eileen's share. Calculate Serene's share.

Help ...... please. How should the answers be presented and is this really a P5 appropriate question?

Thank you very much.

cheers.

MathIzzzFun
KiasuGrandMaster

Posts: 2357
Joined: Wed Mar 09, 2011 11:49 pm
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### Re: Q&A - P5 Math

Trina wrote:
MathIzzzFun wrote:
Trina wrote:Please assist with this question:

There are 40 pupils in a class. Each boy donated \$3 and each girl donated \$2. The boys donated \$30 more than the girls.
How many boys are there?
How many girls are there?

Thanks!

Assume all boys donated, total amount --> 40 x \$3 = \$120
\$120 - \$30 = \$90 --- excess amount to be reduced by girls' donation
Number of girls = \$90/(\$3+\$2) = 18
Number of boys = 40-18 = 22

cheers.

Thanks but still dont get it.. Can provide narration? Thanks

cheers.

MathIzzzFun
KiasuGrandMaster

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### Re: Q&A - P5 Math

this seems quite ingenious, but rather mind bending. Think I'll stick to simultaneous equations.

TheBluePapa
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### Re: Q&A - P5 Math

Yes Speedmath, I got it. Just have to put Serene on the same platform & everything becomes clear.

However this is a "whole number" question. Son hasn't been taught ratio yet so perhaps got to use MathIzzzFun's workings but I wonder how the common numerator 60 come about.

Thank you very much.

Oracle
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