PSLE Maths question. How to solve?

[Jamstart]

Bro, I really dunno leh. I see stars when I see so many words. Maybe you should ask bro Kusje, he said these sums are much simplier.

[Darryn]

Some students find it difficult because they cannot fully understand the question(s). Besides able to solve math problems, one has to be good in the English subject.

 

Worldwide, this is one of the biggest arguments over standardised testing - you are actually testing two subjects in one. Particularly if the exam language is not your mother tongue, you will have difficulties, even if your grasp of the concepts is very sound.

[Darryn]

All those that you posted are much simpler than the one(sweet and chocolate question) that people are complaining about. Took me quite a while(30 minutes) to recall how to draw models to do that which means that if I were taking the PSLE, I'd have gotten the question wrong.

 

Looking at the sweet and chocolate problem, I could quite quickly see how to get the solution via algegra - it is a realtively simple simultaneous equation.

 

Although I would like to add, I really hope that the OP is not a direct quote from the exam paper - if it is, the question is poorly written and also contains grammatical errors.

Edited October 16, 2009 by Darryn

[Yapahfai]

question 1 should be 88kg of rice sold by both.

[Yapahfai]

question 4 answer should be 10.5 min later if I calculate correctly.

 

[Noobcar]

I believe if they can set this type of question, it means that they believe in the abilities of the children taking the exam to solve it.

[Babyt]

Curry puff shop sells puffs at $0.80 each. Offer:Buy 3 get 4th half price. If customer has $50, how many puffs can he buy if he buys as many as he can.

 

my solution = 60 pieces + 20 free = 80 curry puffs

 

based on trial and errors using calculator.

 

if $50/0.8 = 62.5 (u cant buy 1/2 a curry puff so u can buy only 62pcs. but 62/3 =20.8 free puffs (u cant buy 0.8 a curry puff).

 

so i keep trying using 61 and finally 60 pcs as result. ;p

[Yapahfai]

question 6, should be 71 curry puffs?

[Yapahfai]

for question 6, the 4th curry puff is not free lei

 

the 4th curry puff is selling at 40cents for every 3 curry puffs sold.

 

[Darryn]

Curry puff shop sells puffs at $0.80 each. Offer:Buy 3 get 4th half price. If customer has $50, how many puffs can he buy if he buys as many as he can.

 

my solution = 60 pieces + 20 free = 80 curry puffs

 

based on trial and errors using calculator.

 

if $50/0.8 = 62.5 (u cant buy 1/2 a curry puff so u can buy only 62pcs. but 62/3 =20.8 free puffs (u cant buy 0.8 a curry puff).

 

so i keep trying using 61 and finally 60 pcs as result. ;p

 

Not do trial and error, just work out the price for a set, and see how many sets can buy first.

 

After that take the remaining money and see how many single puffs can buy

Edited October 16, 2009 by Darryn

[Carbon82]

Curry puff shop sells puffs at $0.80 each. Offer:Buy 3 get 4th half price. If customer has $50, how many puffs can he buy if he buys as many as he can.

 

my solution = 60 pieces + 20 free = 80 curry puffs

 

based on trial and errors using calculator.

 

if $50/0.8 = 62.5 (u cant buy 1/2 a curry puff so u can buy only 62pcs. but 62/3 =20.8 free puffs (u cant buy 0.8 a curry puff).

 

so i keep trying using 61 and finally 60 pcs as result. ;p

 

You answer is not correct. This is my solution / working.

 

Buy 3 and get 4th at half price. So a set of 4 curry puff is going to cost ($0.80 x 3) + ($0.40 x 0.5) = $2.80

 

With $50, a person can buy $50 / $2.80 = 17.85 set of 4 curry puff, which we have to round it off to 17 set.

 

17 set of 4 curry puff = 68 pcs, at 17 x $2.80 = $47.60

 

So he is left with $2.40, which is just enough for another 3 curry puff and $0.80 each.

 

So total number of curry puff he can buy with $50 is = 68 + 3 = 71

[Yapahfai]

last question, 345 balloons altogether?

[Darryn]

My answers to the questions

 

1. 88 kg of rice has been sold (44kg per shop)

2. by rights 1/14 should be 112, so there should be 1568 chairs, BUT like that then there is not a whole number of chairs in rows of 13...either I am sotong or there is some information missing from the question (telling us chairs are stacked is a clue, but I still cannot work it out)

3. 100 minutes each

4. Totally not enough info to solve, need either the start time, to total distance travelled at halfway point or some other variable

5. 1200 cookies in total

6 Total balloons is 345

Edited October 16, 2009 by Darryn

[Babyt]

You answer is not correct. This is my solution / working.

 

Buy 3 and get 4th at half price. So a set of 4 curry puff is going to cost ($0.80 x 3) + ($0.40 x 0.5) = $2.80

 

With $50, a person can buy $50 / $2.80 = 17.85 set of 4 curry puff, which we have to round it off to 17 set.

 

17 set of 4 curry puff = 68 pcs, at 17 x $2.80 = $47.60

 

So he is left with $2.40, which is just enough for another 3 curry puff and $0.80 each.

 

So total number of curry puff he can buy with $50 is = 68 + 3 = 71

 

OH 4th piece for HALF PRICE, NOT FREE....haha....careless reading...ok ZERO PT.

[Leslielai]

what's going on in here lol

 

 

[Darryn]

what's going on in here lol

 

Dunno about others, but for me I'm exercising muscles I ain't used in about 17 years......and it hurts

[Leslielai]

Dunno about others, but for me I'm exercising muscles I ain't used in about 17 years......and it hurts

 

Heh.

 

For those who struggle to answer your children's primary mathematics questions the primary school way, you may post them in here. I will try my best to answer them all.

[Johnny4305]

for question 4, answer is 11.06am or 21 mins later is it??