Sing Tien Loo
Asked 8 years ago

SG chevron_right Primary 5 chevron_right Measurement

Dear all, this is a P5 qn. Would appreciate it if someone help explain why I can't use 15cm as the base and height? The correct way is to take 1/2 x 18x 15 = 108.Thanks in advance!

Replies 7
Jolyn Low

5 years ago
Jolyn Low

Hi! You cant use the 15cm as the base as the question did not state that the two sides of 15cm are perpendicular to each other. In order for you to apply 1/2 x base x height, base and the height must always be perpendicular to each other. It will be indicated in the question on the diagram via a small square.

5 years ago
Jolyn Low

Hope it helps! :)

5 years ago
Sing Tien Loo

Thanks Jolyn! Originally, I have assumed the 2 sides are perpendicular to each other. We even use a set square to measure. Looks like we can't assume this in a "isosceles" triangle. Your explanation makes me have a new understanding! Thanks very much!!!

5 years ago
Jolyn Low

No problem! An isosceles triangle can sometimes be a right angle triangle too. However it depends on the diagram and instructions given, the child has to be careful when reading the qns. Have a great weekend!

5 years ago
Alex R. S. Chia

Standard disclaimer in all math questions. Diagram may not be drawn to scale.

5 years ago
Sing Tien Loo

Thanks Alex!!

5 years ago

Joy Ce
Asked 8 years ago

SG chevron_right Primary 3 chevron_right Measurement

Help please

Replies 1
Jolyn Low

5 years ago

Rezal Samad
Asked 8 years ago

SG chevron_right Primary 4 chevron_right Number and Algebra

Using algebra answer is 42 for Melvin.. but son still not learn that yet.. how to solve using simpler method..TIA....

Replies 5
Zhong Shu Hao

5 years ago
Rezal Samad

Aiyah.. thanks.. need to go back and learn my sons method.. thanks once again

5 years ago
Zhong Shu Hao

Welcome! 😊

5 years ago
Anni Mae Oribello-Tan

correct! same answer :)

5 years ago
Kelly Thong

5 years ago

Don Wee
Asked 8 years ago

SG chevron_right Primary 3 chevron_right Number and Algebra

P3 maths - kindly advise the non-algebra way. Tks

Replies 3
Zhong Shu Hao

5 years ago
Don Wee

Tks Shu Hao

5 years ago
Zhong Shu Hao

welcome Don Wee

5 years ago

Joy Ce
Asked 8 years ago

SG chevron_right Primary 6 chevron_right Number and Algebra

Pls help me with this question!

Replies 3
Zhong Shu Hao

After 20 coins are transferred to Y, Y has 45 coins. So Y will have 45-20＝25 coins at first. As X and Y have the same number of coins, X will have 25 fifty cents coins while Y have 25 one dollar coins. So Y will have 25x50cents＝$12.50 more than X at first.

5 years ago
Joy Ce

Thks

5 years ago
Zhong Shu Hao

welcome!

5 years ago

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