For ‘N’ and ‘O’ level, it is acceptable to just use the calculator to get the std deviation and give the answer without showing the working, i.e. showing the formula with all the data given?

e.g.
std dev = (5x5) x 15 + (6x6) x 10 +…

Hi, please help.


Mdm A used either butter or margarine for her cakes. The cost of butter was thrice as much as the cost of margarine. She used 60% of butter and 40% of margarine to bake cakes. She spent $220 on the butter and margarine that she had used to bake the cakes. How much would she save if she used 40% of butter and 60% of margarine instead?

Thank You

Thanks, now I see where I went wrong.

Nan Hua 2012 SA1 Paper 2 Question 1


Adrian as 2/3 as many books as Belle. Cindy has 4/5 as many books as Adrian. If Cindy has 64 books, how many books does Belle have?

My answer is 48 but the given answer is 120.
Please help.

Fiona is 3 kg lighter than Eliza and 7 kg heavier than Tina.

If Fiona is j kg, find the total weight of the 3 girls.

This problem sum is taken from last year CA1 paper from a school.
The working j + (j + 3) + (j - 7) = 3j + 3 - 7
This will result in dealing with negative number.
Is this in the PSLE syllabus?

I think not. Look at this website for the approved list of calculators,


http://www.seab.gov.sg/calculatorList/GuidelinesCalculators.pdf

Maybe you can go back to the shop to change.

As a matter of interest, how to sound-proof a room? Thanks.

Peony:

kwcllf:

[quote=\"chyn3471\"]Hi all,

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I've also heard from secondary school teachers of how they have to \"unteach\" the damage done at primary school maths.

They assured me that secondary school maths will not confuse a child the way primary school maths does. Where questions are so ambigious that the difference between right and wrong sometimes lies in language interpretation.

[/quote]I wonder what sort of damage the secondary school teachers are referring to. Maths is Maths. Yes it can be easy and it can be difficult. If a child finds it difficult it might put him/her off Maths but not ‘damage’ a child. Or are the secondary school teachers saying that the primary school teachers are not teaching Maths properly. Of course there are good and bad teachers both in primary and secondary schools.
By the way, I’m not a primary school teacher. I’m a parent whose children have gone through the primary and secondary Maths and I tutor both primary and secondary Maths.

awesomeguy:

Sec 2 Express Math Qn Proportion


For an adventure camp, food is bought to last for 15 days for a group of 40 students. \tIf 4 students left the camp after 6 days, how many days can the food last for the \trem6aining 36 students?

Please help. Thanks

Inverse Proportion,
Days(x) = 15 - 6 = 9
Students(y) = 40
xy = k
9 x 40 = k
k = 360

xy = 360

when y = 36, x(36) = 360
x = 10 (ans)