P5 Problem Sums

last SG · 2012-02-22T22:03:58+00:00

To every parents whose child are taking PSLE.Be happy even if your child scores 200, because they had swifty became the the 50%, which is basically the expre...

Emilybiz SG

Need help with the following problem sum for my kids works...

Question 1

Tins A, B and C each contained some coffee powder. Mr Lim transferred 1/8 of the coffee powder from Tin A to Tin B, then scooped 1/8 of the coffee powder from tin B into tin C and finally transferred 1/8 of the coffee powder from tin c to tin a. Now there are 49g of coffee powder in each tin. How much coffee powder was there in each tin at first?

>> Answer : Tin A 48g, Tin B 50g , Tin C 49g. Right? How to present the answer???

Question 2

Mabel had a total of 128 pieces of $5 notes and $10 notes in her handbag. After she spent 2/7 of her $5 notes and 3/5 of her $10 notes, she had twice as many $10 notes as $5 notes left.

How many $5notes did Mabel spend?

How much did she spend altogether?

Toiletries SG

I admit I was having a little bit of problem with this, given that it's a P5 question and since Algebra is out of the question I think, I opted to go with the table form. Graph would be complicated to explain as the 1/8 ratio is consistent.

And I attempted Question 2 using the graph method.

Emilybiz SG

Cool..! Thanks

FireIce SG

working backwards
tin C - 49g (since trf 1/8 out, now 7/8 = 49)
7/8 = 49
1/8 = 7
8/8 = 56g (after receiving from B)

tin A - 49g (after receiving 7g from C)
before receive from C = 42g (which is after giving 1/8 to B)
7/8 = 42
1/8 = 6
8/8 = 48g (before giving to B)

tin B received 6g from A
then give 7g to C
49 + 7 - 6 = 50g

A = 48g
B = 50g
C = 49g

***********************************************************************************

Mabel had a total of 128 pieces of $5 notes and $10 notes in her handbag. After she spent 2/7 of her $5 notes and 3/5 of her $10 notes, she had twice as many $10 notes as $5 notes left.

How many $5notes did Mabel spend?

How much did she spend altogether?

using ratio,

$5 sp : $5 left
2 : 5

$10 sp : $10 left
3 : 2

make $109 left 2 times of $5 left
(10 u is twice of 5u)

$10 sp: $10 left
15 : 10

2 + 5 + 15 + 10 = 32u
32u = 128 pcs
1u = 4pcs

$5sp = 2u x 4 = $40
$10sp = 15u x 4 = $600

total sp = $640

Sky_Blue223 SG

Wow. Which primary school is this?

Summer hill SG

Wow. Which primary school is this?

all type of school got de.

I find the the way they teach p5s and p6s wrong, use algrebra so much easier to understand.

last time my brain almost explode trying to understand the problem sums

4sg SG

now pri already got simultaneous equations + problem solving + understanding concise english instructions some more........

Summer hill SG

now pri already got simultaneous equations + problem solving + understanding concise english instructions some more........

now pri school very stressed.

i find sec 1 and sec 2 less stress than p5 and p6

4sg SG

now pri school very stressed.

i find sec 1 and sec 2 less stress than p5 and p6

I got two nieces in p4 and p2.

wat yr advise for them when going into p5 and p6?

Sky_Blue223 SG

all type of school got de.

I find the the way they teach p5s and p6s wrong, use algrebra so much easier to understand.

last time my brain almost explode trying to understand the problem sums

I remember the days where my sis would ask me those qns...

As an elder bro, damn paiseh when I don't know how to answer sia... so have to tell her to wait then slowly think...

But this is good. Means kids are getting smarter. Can handle such problems.

4sg SG

you also may wish to know......I have worked with psychiatrist b4.......children seeing psychiatrists more n more n prob getting more and more complex......not a good thing, really!!!

Dalforce 1941 SG

what's the use of learning all this at primary school level? got use or no use?

Summer hill SG

I got two nieces in p4 and p2.

wat yr advise for them when going into p5 and p6?

i remember when i 1st go into P5..i failed my math exams for the 1st time. :o Everyone in class either just pass or fail.

P4 to P5 is a very big jump, its the time when you can no longer slack must study at least a little bit just to pass the exams.

in P5 you realised that problems sums is the greatest enemy. :O Like half of the marks goes to problem sums.

my advise is do a lot of practice on problem sums, and remember must hired tution teacher, otherwise it would be very hard to understand the formulas. also tell their parents to relax if their child failed their 1st test in P5.

4sg SG

i remember when i 1st go into P5..i failed my math exams for the 1st time. :o Everyone in class either just pass or fail.

P4 to P5 is a very big jump, its the time when you can no longer slack must study at least a little bit just to pass the exams.

in P5 you realised that problems sums is the greatest enemy. :O Like half of the marks goes to problem sums.

thnks s h mei mei......

Summer hill SG

i once ask my classmates feel in P6.

they say they wanna suicde because PSLE very stress. i had been there too, i also have thoughts of sucide.

Summer hill SG

what's the use of learning all this at primary school level? got use or no use?

actually, no use leh.

i only pass 1 year everything forget liao

Dalforce 1941 SG

study so much in the end only 23% go uni.

Singapore boasts a highly competitive and well-regarded primary and secondary education system, but the number of Singaporeans completing a tertiary education is relatively low.

Only 23 percent of Singaporean students entering primary school complete a degree at a local four-year university.

In other knowledge-economies such as Japan's, around 50 percent of students complete a university degree.

http://wikileaks.org/cable/2007/02/07SINGAPORE394.html

Summer hill SG

study so much in the end only 23% go uni.

Singapore boasts a highly competitive and well-regarded primary and secondary education system, but the number of Singaporeans completing a tertiary education is relatively low.

Only 23 percent of Singaporean students entering primary school complete a degree at a local four-year university.

In other knowledge-economies such as Japan's, around 50 percent of students complete a university degree.

http://wikileaks.org/cable/2007/02/07SINGAPORE394.html

yah lor. :/

must work hard for a scholarship, i take on bonds so i can go overseas unniversity

Summer hill SG

actually i feel p5 and p6 most stressful years in schooling.

in secondary school, o-level come you can hanfle cos you have the maturity.

P6 sure every kid have sucidal thoughts. just never act it out.

Sky_Blue223 SG

For maths. Learn abacus and creative problem solving. Google them.

Saved my life as my mental sums were (Y) then. Now different story le...