Q&A - PSLE Math

[zsqchx]

Could someone help me to solve Q.27 for Henry Park prelim 2011 paper1? Thank you.

[raghupavithra]

kasey needed to make120 bows for prize giving.she used 12.4 cm to make a bow.she bought 3 rolls of ribbon,each 5 m long.find the lenghth of the ribbon she had left.


how to solve this

[Vanilla Cake]

ozora:

Mr Lee bought some shirts for $425. if He was given a discount of 15%, he would be able to buy 5 more shirts for the same amount of money. What is the original price of shirt?

The original question reads:

Mr Lee bought some T-shirts for $425. If he was given a discount of 15%, he would be able to buy 5 more identical T-shirts for the same amount of money. What was the original price of each T-shirt?

This question had been discussed over http://www.kiasuparents.com/kiasu/forum/viewtopic.php?f=48&t=14433&p=582309. It's from ACS (P/J) 2011 P6 Prelim Maths Paper 2 Q9 - 3marks. When you work backwards and check, the number of T-shirt is not a whole number.

Discount of 15% could buy 5 more T-shirts
Amount spent on the T-shirts = $425 -> 100%
1% -> $425/100 = $4.25
15% -> $4.25x15 = $63.75
So, 5 more T-shirts after 15% discount -> $63.75
1 T-shirt after 15% discount -> $63.75/5 = $12.75
means 85% -> $12.75
1 T-shirt before 15% discount aka original price -> $12.75/85x100= $15.00

[Vanilla Cake]

zsqchx:

Could someone help me to solve Q.27 for Henry Park prelim 2011 paper1? Thank you.

Pls refer to http://www.kiasuparents.com/kiasu/forum/viewtopic.php?f=48&t=14433&p=582309 for the worked solution.

[Publica]

Hi Vanilla Cake,


Can you help to verify the answer for Q12b of Nan Hua Maths preliminary paper? Thanks.

[mrswongtuition]

raghupavithra:

kasey needed to make 120 bows for prize giving.she used 12.4 cm to make a bow.she bought 3 rolls of ribbon,each 5 m long.find the lenghth of the ribbon she had left.

Each bow: 12.4cm
120 bows: 12.4cm x 120 = 1488cm = 14.88m

Each roll of ribbon: 5m
3 rolls of ribbon: 15m

15m - 14.88m = 0.12m left = 12cm left

[zsqchx]

Vanilla Cake:

zsqchx:

Could someone help me to solve Q.27 for Henry Park prelim 2011 paper1? Thank you.

Pls refer to http://www.kiasuparents.com/kiasu/forum/viewtopic.php?f=48&t=14433&p=582309 for the worked solution.

Hi, Vanilla Cake,

Thank you for your help!

[atutor2001]

ozora:

Mr Lee bought some shirts for $425. if He was given a discount of 15%, he would be able to buy 5 more shirts for the same amount of money. What is the original price of shirt?

is it equate 85%=>425
100% -> 500?
then how?

With 15% discount he would have 15/100 x 425 = $637.75 left

This $63.75 can buy 5 more shirts at discounted price.

Discounted price of 1 shirt = 63.75/5 = $12.75

85% -> 12.75
100% -> 100/85 x 12.75 = $15 (original price of 1 shirt)

[Vanilla Cake]

Publica:

Hi Vanilla Cake,

Can you help to verify the answer for Q12b of Nan Hua Maths preliminary paper? Thanks.

Hi Publica,
Sure and answer for Q12b of Nan Hua 2011 P6 Prelim Maths is 20 degree.

[atutor2001]

raghupavithra:

it takes Mr Adams 20 minutes to saw a pole into 5 equal pieces how many minutes would it take him to saw another similar pole into 10 equal pieces?



how to solve this/

To divide a pole into 5 pieces, we need to make 4 cuts only.
To divide a pole into 10 pieces, we need to make 9 cuts only.

4 cuts -> 20 minutes
1 cut -> 5 minutes
9 cuts -> 45 minutes (you will have 10 pieces)