Q&A - PSLE Math

[tianzhu]

Thank you for your help.


How to show that the sum of all angles is equal to 360 degrees?
Q35 RGPS SA2 2007

http://www.wendykoh.com/07/primary6-rgs-maths.pdf

[Tang]

tianzhu:

Thank you for your help.


How to show that the sum of all angles is equal to 360 degrees?
Q35 RGPS SA2 2007

http://www.wendykoh.com/07/primary6-rgs-maths.pdf

Partial c + d + f = 180 degree (triangle)

The other portion of c + b + a + e = 180 degree (triangle, External angle of a triangle = 2 internal opposite angles = a + e)

So all angles add up to 360 degree.

[Tang]

small:

tianzhu:

Hi Dharma


Thanks for the correction.I made a mistake.(use 20% more instead of 120% more)
Price of venision per kg should be $6.55.
Price of beef per kg is $7.20.
Best wishes.

Hi small
Please consider my earlier post as null and void.
The answer is $47.80.
Best wishes

Once again, many many thanks..my DD and I misunderstood the question.

[quote]The cost of 2kg of beef is 120% more than the cost of 1kg of venison. 1kg of mutton costs 20% more than the cost of 1kg of beef.

1 kg of beef ( 160%) vs 1kg of vensison (100%)

120%/2 +100% =160%

:oops:[/quote]
1 kg venison -> 100%

2 kg beef -> 100% + 120% = 220%
1 kg beef -> 220% /2 = 110%

[Muffins]

Tang:

tianzhu:

Thank you for your help.


How to show that the sum of all angles is equal to 360 degrees?
Q35 RGPS SA2 2007

http://www.wendykoh.com/07/primary6-rgs-maths.pdf

Partial c + d + f = 180 degree (triangle)

The other portion of c + b + a + e = 180 degree (triangle, External angle of a triangle = 2 internal opposite angles = a + e)

So all angles add up to 360 degree.

http://www.postimage.org/

[alamak]

[Moderator's note: Topics merged.]


Car A left Town X for Town Y at the same time when Car B left Town Y for Town X. The average speed of Car A was 56km/h and the average speed for Car B was 72km/h. The two cars passed each other at a point 24km from the midway of the two towns. What is the distance between Town X and Town Y? :?:

[alamak]

[Moderator's note: Topics merged.]


Mr Tan bought three times as many badges as toy cars and spent $144 in total. He spent $84 more on toy cars than on badges. Given that a toy car cost $10.40 more than a badge, what is the cost of a badge? :?

[alamak]

[Moderator's note: Topics merged.]


In a school science fair, there were exhibits from Primary 4 to Primary 6. Altogether 25 exhibits came from Primary 5 and 6. If 16 exhibits were not from Primary 6 and 15 exhibits were not from Primary 5, how many exhibits were there altogether?

[James Ang]

these days I am testing P6 students simple questions; such as what fraction is halfway between 1/32 and 1/2, what is the sum of angles for the vertices of a five-sided star and six-sided star, and how many tiles are arranged on 1 side if 60 tiles are used to form the perimeter of a square!

[finder]

Hi, please help. Thank you.


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Ning and Zhongwei jogged to and fro repeatedly along a straight path in a park between two points A and B. Ning jogged at a uniform speed of 4m/s and Zhongwei jogged at a uniform speed of 6m/s. They started jogging from opposite directions at the same time as show below,

A ------------------X-----------------------------------Y--------------------B

They first met one another at point X. The second time they met was at point Y.

a). Given that the distance between X and Y is 160 m. Find the distance between A and B.

b). If they started jogging at 8am, how long did they take to meet again for the third time? (Express your answers in minutes and seconds)

[oceandeep]

[Moderator's note: Topics merged.]


Gina, Hans, Ian and June bought a present for their mother. Gina paid 2/5 of what the rest paid. Hans paid 1/2 of what the rest paid. Ian paid 1/3 of what the rest paid. June paid $30 less than Ian. how much did the present cost?