Q&A - PSLE Math

[tianzhu]

Hi girl


For Q7, it’s a very common question using listing.

I am sure you can do it.

Wishing you the very best for your exams.

Best wishes

[Michaelia0816]

tianzhu:

Michaelia0816:

14) There were some men and woman in the train. Aft 30 men alighted from the train, the percentage of woman increased from 30% to 45%. How many people were there in the train after 30 men had alighted?

Hi

The number of women stays the same before and after. Make the number of units for women the same.

At first
Men ------- 7 ---------- 21
Women ------- 3 --------- 9

In the end
Men ------- 11
Women ------- 9

10 units ------- 30
1 unit -------- 320*3 -------- 60 (number of people@end)

Best wishes

How to do get it from and statements pls.

[Michaelia0816]

tianzhu:

Hi girl


For Q7, it's a very common question using listing.

I am sure you can do it.

Wishing you the very best for your exams.

Best wishes

May I know what the answer? I would like to know.

[tianzhu]

Michaelia0816:

How to do get it from and statements pls.

Hi

30% -------- 3 units (women)
70% -------- 7 units (men)

Compare before and after

21 – 11 ------- 10

10 units ------- 30 (30 men alighted)

Best wishes

[Michaelia0816]

:hi5: :thankyou:

[tianzhu]

Michaelia0816:

May I know what the answer? I would like to know.

Hi

I did it in a rush, please check.

The answer is 157.

Good luck.

Best wishes

[Michaelia0816]

tianzhu:

Michaelia0816:

16) Daniel had 40% as many marbles as Ethan. Daniel gave away 8 marbles to his brother and Ethan lost 40 marbles of his marbles in a game. Then, Daniel had half as many as Ethan.

A) How many marbles did Daniel have at first?
B) How many marbles did Ethan have at first?

Hi

You may use “Units and Parts”

At first
Daniel : Ethan -------- 2units :5 units

Change
Daniel : Ethan -------- -8 : -40

In the end
Daniel : Ethan -------- 1 part :2 parts

Equalise the parts

2 units – 8 ------- 1 part
(x2)
4 units – 16 -------- 2 parts

4 units – 16 -------- 5 units – 40
1 unit ------- 24Daniel@first -------- 48
Ethan@ first -------120

You may apply the same method for Q13.

Best wishes

I do not quite understand, but equalise the part in Q13 is strange because it got 3 part in 4u-15 but 1 part is 1/1/3-5 ???
I understand this type of question as the part 1 and 2 is simple.

Pls help in the Q13, parts only!!!

[Michaelia0816]

tianzhu:

Michaelia0816:

May I know what the answer? I would like to know.

Hi

I did it in a rush, please check.

The answer is 157.

Good luck.

Best wishes

Same as me!!!! Just for checking, do not rush, I got alot of time.

[tianzhu]

Michaelia0816:

Pls help in the Q13, parts only!!!

Hi

For Q13

At first
Joe:Rachel --------- 4units:3 units

Change
Joe:Rachel --------- 15 :8

In the end
Joe:Rachel --------- 3 parts:2 parts

4 units + 15 -------- 3 parts
(x2)
8 units + 30 -------- 6 parts

3 units + 8 -------- 2 parts
(x3)
9 units + 24 -------- 6 parts

8 units + 30 -------- 9 units + 24

1 unit -------- 6

Joe@first --------- 24

Best wishes

[Michaelia0816]

thank you again, i think I a bit too stubborn abot the parts, forget it could be equalised, i try not to do it in my examination!