Q&A - PSLE Math

[Ender]

Kindly assist with this :

At a fun-raising event, 60% of the people were male and the rest were female. 20% of the female left the event in the afternoon.
In the evening, after 33 male and 35 female left the event, 75% of the people at the event were male.
a) What percentage of the people left the event in the afternoon ?
b) How many people were there at the start of the fun raising event ?

It has been answered before.
http://www.kiasuparents.com/kiasu/forum ... 7#p1703327
http://www.kiasuparents.com/kiasu/forum ... 6#p1682926

[lynn01sg]

Pls help:

Raina saves her allowance by putting a note into her money box each week. Each note was either a $2 note or a $5 note. Her father also puts in a $10 note every 30 days. The total amount she collected after 365 days was $278. How many of the notes were $5 notes?

[nicnac]

Pls help:

Raina saves her allowance by putting a note into her money box each week. Each note was either a $2 note or a $5 note. Her father also puts in a $10 note every 30 days. The total amount she collected after 365 days was $278. How many of the notes were $5 notes?

No of $10 notes -> (365/30) 12
Amount -> $120

$278 - $120 -> $158

Assume all $2notes,

52 * 2 -> 104

158 - 104 -> 54

54/3 -> 18 ($5 notes)

There were 18 $5 notes.

[lynn01sg]

Thanks nicnac, do you know why the last part that you need to divide by 3 which gives you $18 ($5 notes)?

[nicnac]

Thanks nicnac, do you know why the last part that you need to divide by 3 which gives you $18 ($5 notes)?

Difference: $5 - $2 -> $3

[Ender]

Thanks nicnac, do you know why the last part that you need to divide by 3 which gives you $18 ($5 notes)?

This method is call supposition or make a supposition or assumption . Google the bolded keyword, there are many article and youtube examples.
Once you study it you'll understand why we use the difference.

[SOS mum]

Ps help. Many tks and God Bless:)

Meili had some red, blue and yellow balloons. 58 of her balloons were red and 4/11 of them were blue. She had 16 fewer yellow balloons than blue balloons. How many blue balloons did she have?

[nicnac]

Ps help. Many tks and God Bless:)

Meili had some red, blue and yellow balloons. 58 of her balloons were red and 4/11 of them were blue. She had 16 fewer yellow balloons than blue balloons. How many blue balloons did she have?

Blue -> 4u

The balance -> 7u -> red + yellow

7u -> 58 + ( 4u -16)
3u -> 42
U -> 14

Blue -> 4u -> 56

[SOS mum]

Tks..Ninac..Appreciate greatly

[nicnac]

Tks..Ninac..Appreciate greatly

You're welcome