leo_mums:

http://i57.tinypic.com/2mmzrrs.jpg\">

a) perimeter = circumference of small circle (see top+bottom) + curcumference of mid-sized circle (see left+right) + circumference of largest circle (see inside circle) = 6pi + 8pi + 10pi = 24pi cm
b) similarly, shaded area = small circle + mid-sized circle + rectangle - largest circle
=3x3pi + 4x4pi + 6x8 - 5x5pi = 48 sq cm

leo_mums:

http://i58.tinypic.com/2ujmbsm.jpg\">



Please help. Thank you.

a) Diagonal QS bisects the right angle. Angle x = 45-19 = 26 deg
b) Triangle RST is an isosceles triangle with angles 26 deg, 77 deg and 77deg.
Angle QRT = 90-77 = 13 deg
Angle y = 360-225-13-90 (Angle sum of quadrilateral TRQP) --> NB: doesn't matter is one of the angles is >180deg. Ans: 32 deg

leo_mums:

http://i58.tinypic.com/1zb9phz.jpg\">


Please help. Thank you.

G may look like midpoint of DC but it may not be. It doesn't matter.
Looking at triangle AGC (base of GC), child needs to imagine and understand that as vertex A moves along AB to B, area of triangle AGC is still the same (same base GC, same height AD).

So, area of the two \"white\" triangles when they do not overlap is half the area of rectangle (=480 sq cm). When they overlap like the above, the white part is 410 sq cm (480-70).
The shaded part will then be 550 sq cm (480+70).

Ratio is 550:410=55:41.

Wgh2005:

Hi, can anyone kindly help me on the below two questions. Thank you.


http://i60.tinypic.com/6qfgog.jpg\">

Another one as below:

http://i61.tinypic.com/9sh4lk.jpg\">

Hi. Alternative presentation with models if kid has not learned solving equations yet. Hope it helps.
(Edit: final answer for q1 is $420, sorry)
http://i60.tinypic.com/wcomm1.jpg\">
http://i58.tinypic.com/11icnfa.jpg\">

Nebbermind:

SAHMom:

Area of A is 36 sq cm and Perimeter is 14x4 + 8x2 = 72 cm (helpful if child sees the perimeter this way).

Good one!
Your kid taking psle too?

Thanks! Yes, my kid (\"and I too\") taking PSLE. Have learnt a lot from many parents here.
If the math working is too complex for a P6, it probably is too complex for a P6.
I try to think like a P6 before I coach my child.

Ilye:

The figure consists of 3 squares. The total area of the figure is 296cm2. Assuming that all the length of the squares are in whole numbers, find

(a) The area of the smallest square
(b) The perimeter of the figure
http://i61.tinypic.com/2j2urex.png\">
please help ...:?:

http://i60.tinypic.com/349fhp1.jpg\">

Area of A is 36 sq cm and Perimeter is 14x4 + 8x2 = 72 cm (helpful if child sees the perimeter this way).

Swift Formula:

(100% - something) refers to the empty space beside the bar, compared to 100%

So we find all the empty space of all the bars except last 1.
Take the last bar minus all the empty space = x% (Do note if x is negative, take x to be 0)
)

Yup I understand now. Thanks, Swift Formula.

Swift Formula:

Circle intersecting for 3 still ok but i still feel it can get complicated. As the number rises, it's impossible to draw 5 or 10 circles.


Bars are more simple for students to understand since students learn model + units since young. Because model + units are the easiest way to present the question to students. After they understand the concept, u can throw any % and any amount of category, they will be able to solve it.

Hi Swift Formula, noted. Venn diagram is not in p6 syllabus while it helps me and my child understand the concept of limiting total population to 100%. If you ask me, I can't draw four or more intersecting circles right now so I might have never learnt to or forgotten how to. And pardon me for asking a stupid question, what is the rationale to have your last working as \"Take the last value minus the sum of the 2 remaining value. u can get the minimum value for x\" ? What is the key concept or understanding here? Thanks!

Xtintedcandies:

In a primary school, 75% of the pupils plays badminton, 70% play basketball and 65% play tennis. Given that at least x% of the pupils play all three games, find the value of x.


Please help me. Thanks

It's easier to understand by drawing a Venn Diagram with 3 intersecting circles.
Else can go by logic below.
Logic is total population 100%.
75% + 70% + 65% = 210%.
The overlapping area (like a flower with 3 petals in Venn Diagram) is 110% (210% -100%), represents those who played at least 2 games or all 3 games.
As total population can only be 100%, deducing at least 10% play all 3 games. The the rest 90% play 2 games. And no one plays only 1 game or 0 game.

Just for interest. the centre overlapped area (x) (i.e. those who play all 3 games) can be more but not less than 10% due to above logic. As x increases, say to 11%, 99% (=110% - 11%) play 2 or 3 games, and then 1% play only 1 or 0 games.

belnanna:

Please help on this question. Appreciated deeply! Thanks in advance!


Mrs Amos baked 30 more chocolate cookies than almond cookies.After selling 2/5 of the chocolate cookies and 3/4 of the almond cookies, she had 39 more chocolate cookies than almond cookies left. How many chocolate cookies did she bake at first?

5C-4A=30......(1)

Remainder:
3C-1A=39
12C-4A=156.....(2)

(2)-(1):
7C=126
C=18, A=15
5C+4A=90+60=150

Or let Almond cookies be 20u, chocs 20u+30
Remainder is 5u of Almond and 12u+18 of chocs
Difference is 7u+18,=39
u=3
Total 40u+30=150