Q&A - PSLE Math

[fruitionlearnin]

Hi Bunny27,


Is your question complete?

The fruit seller had the same number of apples, oranges and pears at first. After he had 90 fruits left. --> Did he sell all 3 types of fruits or only sell one/two types??

If he sells all 3 types, then there is no solution to ur question.

[tianzhu]

2DMommy:

3)Mr Singh had $315 worth of concert tickets. He sold 4 adult tickets and 3 child tickets. Each adult ticket is 1 1/2 times as much as a child ticket. If the value of the tickets Mr Singh had left is 3/7 of the original amount, what is the cost of a child ticket ?

Hi

You may use “Number*value”.

Value of adult ticket ----- 3 units
Value of child ticket ------ 2 units

Adult’s concert tickets ------ 4*3 ------ 12 units
Child’s concert tickets ------ 3*2 ----- 6 units

Total number of units ----- 18 units

Value of tickets sold ----- 4/7*315 ------ 180

18 units ------ 180

1 unit ----- 10

Cost of child ticket ----- 2 units ------ 2*10 ----- 20

Best wishes

[MathIzzzFun]

2DMommy:

Please help me with these questions :


1)There were some $5 , $10 and $50 notes in Jane's wallet. The value of the $5, $10 and $50 was in the ratio 3 : 4 : 2. After spending 50% of her $50 notes, 10 of her $10 notes and 2/3 of her $5 notes, Jane had $200 left. Find the total amount of money Jane had in her wallet at first.



Thank you and Happy New Year !

Hi

Q1...http://i41.tinypic.com/j624pw.jpg\">

cheers.

[2DMommy]

Dear Tianzhu and MathIzzzFun


Many thanks for the reply and Happy New Year !

[Petkwang]

Hi All,


Can someone help to solve these questions by using model. Thank you.

A total of 510 people visited a book exhibition,. 5/8 of the male visitor and 1/3 of the female visitors were adults. There were twice as many girls as boys. How many more men than women visited the book exhibition?


There are 98 pieces of $20 notes and $50 notes in a drawer, A cashier took out 3/4 of the $50 notes and put in another ten $20 notes. As a result, the number of $20 notes was five times the number of $50 notes. What was the total value of the $20 notes in the drawer at first?

[MathIzzzFun]

Petkwang:

Hi All,


Can someone help to solve these questions by using model. Thank you.

A total of 510 people visited a book exhibition,. 5/8 of the male visitor and 1/3 of the female visitors were adults. There were twice as many girls as boys. How many more men than women visited the book exhibition?


There are 98 pieces of $20 notes and $50 notes in a drawer, A cashier took out 3/4 of the $50 notes and put in another ten $20 notes. As a result, the number of $20 notes was five times the number of $50 notes. What was the total value of the $20 notes in the drawer at first?

Hi

Q1.
Number of boys : men --> 3u : 5u
Number of girls : women --> 6u : 3u
Total number of visitors --> 17u -- 510
1u --> 30
2u --> 60, there were 60 more men than women

Q2.
In the end, number of $20 notes : $50 notes --> 5u : 1u
At first, number of $50 notes --> 4u
5u + 4u = 9u --> 98 + 10 = 108
9u --> 108
1u --> 12
Number of $20 notes at first --> 5u - 10 = 50, value of $20 notes --> 50 x $20 = $1000

cheers.

[homeworkmummy]

Is there something wrong with the following question? The question is extracted from Ai Tong paper CA1 2011. The total is actually more than 100%…


In a survey, some pupils were asked if they preferred volleyball or table tennis. 13/20 of the pupils chose volleyball, 75% of the pupils chose table tenis and 5% of the pupils did not chose any of the two sports. Given that 90 pupils chose both volleyball and table tennis, how many pupils took part in the survey?

[elkniwt]

homeworkmummy:

Is there something wrong with the following question? The question is extracted from Ai Tong paper CA1 2011. The total is actually more than 100%....


In a survey, some pupils were asked if they preferred volleyball or table tennis. 13/20 of the pupils chose volleyball, 75% of the pupils chose table tenis and 5% of the pupils did not chose any of the two sports. Given that 90 pupils chose both volleyball and table tennis, how many pupils took part in the survey?

Hi homeworkmummy,

This question is a venn diagram type of question. To find the overlap between volleyball and table tennis, take 3/4 + 13/20 - (1 - 1/20) = 9/20
9/20 -> 90 pupils
1/20 -> 10 pupils
20/20 -> 200 pupils
Hence, 200 pupils took part in the survey.

Regards.

[MathIzzzFun]

homeworkmummy:

Is there something wrong with the following question? The question is extracted from Ai Tong paper CA1 2011. The total is actually more than 100%....


In a survey, some pupils were asked if they preferred volleyball or table tennis. 13/20 of the pupils chose volleyball, 75% of the pupils chose table tenis and 5% of the pupils did not chose any of the two sports. Given that 90 pupils chose both volleyball and table tennis, how many pupils took part in the survey?

Hi

use Venn Diagram to solve.

5% did not choose any of the sports --> 95% chose either table-tennis or volleyball or both

75% chose table tennis --> (95% - 75%) = 20% chose volleyball only.
65% chose volley ball --> (65%-20%) = 45% chose both volleyball and table tennis
45% --> 90, 1% --> 2, 100% --> 200
200 pupils participated in the survey.

cheers.

[homeworkmummy]

Hi Elkniwt and MathIzzzFun, thank you so much for your help!