Q&A - PSLE Math

[Ichigokun]

Oh my god. I just realised after going to Secondary School I forgot how to do Primary School math!! WAHAHAHA. Forgotten everything during the hols after PSLE.

[MathIzzzFun]

fightingmom:

Please help:


Mrs Tan bought some fruits. 1/9 of the fruits were pears, 3/4 of the remaining fruits were oranges and the rest were mangoes. The prices of the fruits were as shown below:

Pears : $0.60 each
Oranges : $0.45 each
Mangoes : $1.50 each

She spent $19.80 on the pears and mangoes. How much did she spend on the mangoes?

Hi

I think the $19.80 is spent on pears and oranges, otherwise Mrs Tan would have bought 1/2 a pear

1) $ 19.80 spent on pears and mangoes

number of pears, oranges and mangoes --> 1 : 6 : 2

1 pear + 2 mangoes --> $ 0.60 + $ 1.50 x 2 = $ 3.60
$ 19.80 / $ 3.60 = 5.5
number of pears --> 5.5
number of oranges --> 6 x 5.5 = 33
number of mangoes --> 5.5 x 2 = 11
amount spent on mangoes = 11 x $ 1.50 = $ 16.50

2) $ 19.80 spent on pears and oranges

1 pear + 6 oranges --> $ 0.60 + $ 0.45 x 6 = $ 3.30
$ 19.80 / $ 3.30 = 6
number of pears --> 6
number of oranges --> 6 x 6 = 36
number of mangoes --> 2 x 6 = 12
amount spent on mangoes = 12 x $ 1.50 = $ 18

cheers.

[anneshirleygilbert]

Hello tianzhu,


1) Susan has some vanilla and chocolate sweets in her bag. If she adds 20 vanilla sweets into the bag, the percentage of vanilla sweets in the bag becomes 40%. If she adds 30 chocolate sweets, there will be 70% of chocolate sweets in the bag. How many vanilla and chocolate sweets does she have? (P6 2010 SA2 River Valley P2 Q18)

My answer for the above question is 70 sweets, is it correct?

2) Mrs Lim bought some bowls and plates. If she buys another 5 bowls, there are 60% as many bowls as plates. If she buys another 9 plates, there will be thrice as many plates as bowls. How many bowls did she buy? (CHS P5 SA2 2009) ----- (answer is 13)

I can’t do the second question. My answer is a fraction, so I know it can’t be correct. Please help.

[tianzhu]

Hi anneshirleygilbert


The answers ----- Vanilla sweets: 72 and Chocolate sweets: 138.

For the question on bowls and plates, you may use MD or UM.

Due to time constraints, I’ve posted the solution using UM instead of MD.

Hope this helps.

Best wishes

http://farm8.staticflickr.com/7146/6728816353_e2a7aca824_z.jpg\">

[Bunny27]

tianzhu:

Hi anneshirleygilbert


The answers ----- Vanilla sweets: 72 and Chocolate sweets: 138.

For the question on bowls and plates, you may use MD or UM.

Due to time constraints, I’ve posted the solution using UM instead of MD.

Hope this helps.

Best wishes

http://farm8.staticflickr.com/7146/6728816353_e2a7aca824_z.jpg\">

Hi,
I'm not sure about this question....can someone help me?
Thanks !
A fruit seller had the same number of apples, oranges and pears at first. After he had 90 fruits left. There were 15 fewer pears than apples left. The number of apples left was twice as many as the number of oranges left. How many oranges did he sell?

[Bunny27]

Hi, not sure about this question…can someone help me?

Thanks !
A fruit seller had the same number of apples, oranges and pears at first. After he had 90 fruits left. There were 15 fewer pears than apples left. The number of apples left was twice as many as the number of oranges left. How many oranges did he sell?

[tianzhu]

Bunny27:

Hi,
I'm not sure about this question....can someone help me?
Thanks !
A fruit seller had the same number of apples, oranges and pears at first. After he had 90 fruits left. There were 15 fewer pears than apples left. The number of apples left was twice as many as the number of oranges left. How many oranges did he sell?

Hi

Good Morning.

I guess some information might be missing from your question.

Maybe, it might be something like this, After xx pears and some apples and oranges were sold, he had 90 fruits left.

Please check with your source again.

Best wishes

[Vanilla Cake]

Bunny27:

A fruit seller had the same number of apples, oranges and pears at first. After he had 90 fruits left. There were 15 fewer pears than apples left. The number of apples left was twice as many as the number of oranges left. How many oranges did he sell?

tianzhu:

I guess some information might be missing from your question.
Maybe, it might be something like this, After xx pears and some apples and oranges were sold, he had 90 fruits left.
Please check with your source again.

The above question has missing information and is adapted from the PSLE 2008 Maths exam:

A restaurant had the same number of apples, oranges and pears at first.
After 38 pears, some apples and oranges were used, there were 90 fruits left.
There were twice as many apples as oranges left. The number of pears left was 15 fewer than the number of apples left.
How many oranges were used?

[tianzhu]

Hi


Based on VC’s reply, if your question is written as;

A fruit seller had the same number of apples, oranges and pears at first. After 38 pears, some apples and oranges were sold, there were 90 fruits left. There were 15 fewer pears than apples left. The number of apples left was twice as many as the number of oranges left. How many oranges did he sell?

The answer is 44 oranges.You may use UM or MD.

Since this is similar to a past PSLE question, you should be able to see the solution from the PSLE 5 years series book.

Best wishes

[YumYum]

Hi, I need help for the following Qn:


If the price of a Barbie doll is reduced by 25%, a loss of $1.20 will be incurred.
If its price is reduced by 10%, a profit of $0.30 will be incurred.
Find the loss or profit incurred if a barbie doll is sold for $13.40.

Thank you.