Q&A - PSLE Math

[cimman]

happyheart:

Hi, one more please. I am always confused when there is transfer back and forth.Thanks.


Jack and Aqil had some game cards. If Jack gave Aqil 52 cards, he would have the same number of cards as Aqil. If Aqil gave Jack 34 cards, the ratio of the number of cards Aqil had to the number of cards Jack had would be 3:7.How many cards did Jack have at first?

actually, you should see this as a Double If question rather than a back and forth transfer question. Double If question is easy to recognize because there are 2 Ifs in the question. The key thing to note in Double If question is the starting point (Before) is the same in both If cases. Work your way up to the Before values in both cases (each If statement is a case) and equate them together.

[YumYum]

Hi, can anyone pls help with these qns:


1) there were 900 more chocolates than lollipops in a candy shop.
After the shop ordered more lollipops and sold some chocolates, the number of lollipops increased by 20% and the number of chocolates decreased by 30%.

Given that there were 370 more lollipops than chocolates in the end, find the total number of chocolates and lollipops in the shop at first.


2) Sonia has some money to buy some photo albums and photo frames.
If she buys 7 similar photo albums and 3 similar photo frames, she will be short of $27.10.

If she buys 2 similar photo albums and 5 similar photo frames, she will have $19 left.

If a photo frame costs $8.20, how much money does Sonia have?

Thanks 

[jieheng]

YumYum:

Hi, can anyone pls help with these qns:


1) there were 900 more chocolates than lollipops in a candy shop.
After the shop ordered more lollipops and sold some chocolates, the number of lollipops increased by 20% and the number of chocolates decreased by 30%.

Given that there were 370 more lollipops than chocolates in the end, find the total number of chocolates and lollipops in the shop at first.


Thanks 

1)

At first
C 10u + 900
L 10u

the number of chocolates decreased by 30% --> - (3u + 270)

the number of lollipops increased by 20% --> + 2u

C 10u + 900 - (3u + 270) --> 7u + 630

L 10u + 2u --> 12u

Given that there were 370 more lollipops than chocolates in the end

12u - (7u + 630) --> 370
5u --> 1000
1u --> 200

the total number of chocolates and lollipops in the shop at first

20u + 900 --> 20*200 + 900 = 4900 (Ans)

[jieheng]

YumYum:

Hi, can anyone pls help with these qns:



2) Sonia has some money to buy some photo albums and photo frames.
If she buys 7 similar photo albums and 3 similar photo frames, she will be short of $27.10.

If she buys 2 similar photo albums and 5 similar photo frames, she will have $19 left.

If a photo frame costs $8.20, how much money does Sonia have?

Thanks 

If she buys 7 similar photo albums and 3 similar photo frames, she will be short of $27.10

3 similar photo frames --> 3*8.2 = 24.6

If she buys 7 similar photo albums only , she will be short of $2.50
(27.1 - 24.6 = 2.5)

If she buys 2 similar photo albums and 5 similar photo frames, she will have $19 left.

5 similar photo frames --> 5*8.2 = 41

If she buys 2 similar photo albums only, she will have $60 left.
(19 + 41 = 60)

Price of one photo album = (2.5+60)/5 = 12.5

the money that Sonia has = 2*12.5 + 5*8.2 + 19 = 85 (Ans)

[YumYum]

Jieheng, thanks for the help 

[Jolyn]

55% of the spectators at a football game were men. 4/5 of the remaining spectators were women and the rest were children.

A)How many percent of the spectators were women?
B)How many percent of the spectators were children?

[tianzhu]

Jolyn:

55% of the spectators at a football game were men. 4/5 of the remaining spectators were women and the rest were children.

A)How many percent of the spectators were women?
B)How many percent of the spectators were children?

Hi

Men ------ 55%

45% remaining

Women ------- 4/5 of 45% ------- 36%

Children ------- 1/5 of 45% ------ 9%

Best wishes

[imacsg]

Can anyone help? Thanks.

A shop sold cupcakes at $2.50 each and tarts at $5.30 each. Apple bought some cupcake while Mark bought some tarts. Mark spent $5.20 more than Apple but bought 8 fewer items than her.

How many tarts did Mark buy?
How much money did Apple spend?

[MathIzzzFun]

imacsg:

Can anyone help? Thanks.

A shop sold cupcakes at $2.50 each and tarts at $5.30 each. Apple bought some cupcake while Mark bought some tarts. Mark spent $5.20 more than Apple but bought 8 fewer items than her.

How many tarts did Mark buy?
How much money did Apple spend?

assume that Mark bought same number of tarts --> 8 more
8 x $5.30 = $42.40
$42.40 + $5.20 = $47.60 --> Mark would have spent $47.60 more than Apple he bought same number of tarts as cupcakes bought by Apple.

$5.30 - $2.50 = $ 2.80 --> 1 tart cost $ 2.80 more than a cupcake.
Number of cupcakes bought by Apple = $47.60 / $ 2.80 = 17
Apple spent --> 17 x $2.50 = $42.50
Number of tarts bought by Mark = 17 - 8 = 9

cheers.

[imacsg]

Thanks for your help.