Pr 6 maths (SA1)

likeyou SG

Hi Everybody, plse help me to solve the below questions, I am not sure how to do and explain to my kids.

1) A shop gave different discounts to different customers. Wanwen paid $96 for a dress after a discount of 20% but Dawn paid $102 for the same dress. How much discount was given to Dawn?

2)A recreation club organised a farm trip for its members. The cost per person was $18. However, 10 members could not go for the trip. Those making the trip then had to pay $24 each. How many members went for the trip?

3) 480 pupils in primary Five are asked to choose ball games and/or swimming as their CCA. 295 pupils take part in ball gams. 267 pupils take part in swimming. 100 pupils take part in both. How many pupils do not choose wither of the two CCAs?

4) There are many 3-digit numbers that are each divisible by 7 and also by 8 without a remainder in each case. What is the largest of these 3-digit numbers?

5)1kg of prawns cost as much as 1.5kg of fish. Lena paid $65 for 2kg of fish and 3kg of prawns. What was the cost of 1 kg of fish?

Please help me as my son next week having SA1 examinations.

Thanks for everybody help and kindness.

Best regards.

@LikeYou

-StarDust- SG

wah nowadays problemns sums like maths olympic

likeyou SG

Hi Star, yes, please help me. I am really lost and gonna drop my hair more...the more I read the more I ke-siao.

Please everybody, help me.

ThunderFbolt SG

1. If she got the dress for $96 after a discount of 20%, it means you would have to divide $96 by 80% (meaning 96 / 80 * 100) to get the original price. Then just compare original price with what Dawn paid.

2. Let number of students going be "x". Meaning 18(x+10) = 24x. Find x.

Not sure how to do the model method with this though.

3. If 100 pupils took part in both, that means 195 pupils only took part in ball games and 167 only took part in swimming. So 100+195+167 is all the students having CCAs.

4. Largest possible number 3 digit number is 999. 7 x 8 = 56. 999 divided by 56 is 17.839. Round down (always round down, even if .999...), multiply by 56 and that's your answer.

5. Let price of 1 kg of prawns or 1.5 kg of fish be 1 unit. There Lena bought 4 and one-third units. 1 kg of fish is two-thirds of a unit. Simple division work.

ThunderFbolt SG

-edited out-

wee_ws SG

Hi,

I feel that Q4 does not suit the pri sch level. It's about divisibility, a subtopic of number theory which is an undergrad course. Thanks.

Cheers,
Wen Shih

wee_ws SG

Hi,

I will help to answer Q1.

80% -> $96, so 1% -> $96/80 = $1.20.

Now $(102 - 96) = $6 = $(1.20 x 5), which represents 5%.

Discount given to Dawn = (20 - 5)% = 15%.
[ Because Dawn pays more than Wanwen. ]

Dawn was given a discount of 15%.

Thanks!

Cheers,
Wen Shih

baiyun SG

Hope this helps.Wishing you good luck in your exams.Best wishes

baiyun SG

Hope this helps.Best wishes.

SBS n SMRT SG

Hi,

I feel that Q4 does not suit the pri sch level. It's about divisibility, a subtopic of number theory which is an undergrad course. Thanks.

Cheers,
Wen Shih

trial and error is the only way

just like

1+3+5+7 ... +111 need to use AP to evaluate, SEAB just lamely says is in syllabus

likeyou SG

Hello everybody,

Thank you so much for all the help and time to solve the problems.

I really dont know how.

Now, I will ask my son to read thru together with me and hopefully, he able to understand it.

Many many million thanks for everybody help.

Yours faithfully

@LikeYou