## Questions on percentages - P5

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### Questions on percentages - P5

Hi,

I come across this question in an assessment book and depending on your interpretation, the answers are different. Would you share what you would have interpreted in this case ?

Question:
Wilson's money was 40% of the amount Ann and Betty had. Ann had 4 times as much as Betty. Wilson had \$420. Ann spent \$294. What percentage of her money did she spend ? Express your answer to 1 decimal place.

Did you get 35% or 58.3% ?

lizawa
BrownBelt

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I got 35%.

3greatkids
OrangeBelt

Posts: 59
Joined: Mon Jul 20, 2009 12:27 pm
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I've got 35% too.

dido
OrangeBelt

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Joined: Sun Jul 05, 2009 4:45 pm
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35%

3Boys
KiasuGrandMaster

Posts: 5014
Joined: Tue Sep 02, 2008 5:28 pm
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My first attempt is also 35%.

This is the answer from the assessment book.

Wilson -> 40%
Ann-> 4units
Betty -> 1 unit

Ann+ Betty -> 60%
5u = 60%
1u = 60/5 % = 12%

Betty = 12%
Ann = 48%

40% -> \$420
48% -> \$(420/40) * 48 = \$504

% spent = 294/504 *100 = 58.3%

So, this question assumes that the total amount of money = 100%
Ann and Betty get 60%; Wilson 40%.

Doesn't seem too right to me. Is there anyway to rephrase the 1st sentence, such that it means what the answer says ?

lizawa
BrownBelt

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Joined: Tue Apr 22, 2008 11:29 am
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Also 35%.

One way to know if the answer is right or not is to substitute backwards both answers and see if you can get \$420. The one that cannot will be the wrong answer.
Guest

The first sentence is wrong if it wants the working to be like what you have shown.

It should state:

Wilson has 40% of a sum of money while Ann and Betty together has the other 60%.

If based on original statement, it means that Wilson has 40% of what Ann and Betty (100%) has.
Guest

ks2me wrote:The first sentence is wrong if it wants the working to be like what you have shown.

It should state:

Wilson has 40% of a sum of money while Ann and Betty together has the other 60%.

If based on original statement, it means that Wilson has 40% of what Ann and Betty (100%) has.

Thanks for this suggestion. This shows that we cannot blindly follow the answers in assessment books.

lizawa
BrownBelt

Posts: 665
Joined: Tue Apr 22, 2008 11:29 am
Total Likes: 0

lizawa wrote:
ks2me wrote:The first sentence is wrong if it wants the working to be like what you have shown.

It should state:

Wilson has 40% of a sum of money while Ann and Betty together has the other 60%.

If based on original statement, it means that Wilson has 40% of what Ann and Betty (100%) has.

Thanks for this suggestion. This shows that we cannot blindly follow the answers in assessment books.

You are welcome. It is quite often we come across publications with errors. If you want to take another step, you can alert them then they can rectify this in their next print.
Guest