Q&A - PSLE Math

[Neat]

o..in that case, I think the original question is likely about money instead of toys...I have changed the toys to $$ below....


Mr Samad had some money. He spent 20% of the money on Monday. He spent $27 on Tuesday. On Wednesday he spent 10% of the remaining money. After that he found that the money he had left was $1 more than 1/2 the original amount he had. How much money did he have at first ?

Original amount --> 10u
Spent on Monday --> 2u, Left --> 8u
Spent on Tuesday --> $27, Left --> 8u - $27
Spent on Wednesday --> 0.8u - $2.70, Left --> 7.2u - 24.30

So, 7.2u - $24.3 = 5u + $1
1u --> 11.5
Original amount --> 10 x $11.5 = $115

cheers.[/quote]

Thanks MathIzzzFun :thankyou:

[the shadowed snake]

Michaelia0816:

Ken answer:

Tianzhu---49
Michaelia0816---24

I cannot understand why.

Hi, I did this Q and I got 48. Is this the ans?

[Essential]

Hi please help… Q10) given that 2/3 of xiacer "s money is equal to 75 percent of Ian"s money , what fraction of ian "s money is the total sum of money

[speedmaths.012624com]

Essential:

Hi please help.... Q10) given that 2/3 of xiacer \"s money is equal to 75 percent of Ian\"s money , what fraction of ian \"s money is the total sum of money

Hi,

One possible solution:

2/3 x Xiacer = 3/4 x Ian

(Use equal/common numerators)

6/9 x Xiacer = 6/8 x Ian

(Now look at the denominators)

Xiacer = 9 uints
Ian = 8 units
Total = 17 units

Can you solve from here?

Cheers


speedmaths.com


.

[whitety]

Hi, need help on 2 qns.


1) Mr Tan has some apples and oranges in the ratio 4: 5. After selling 170 apples and 25% of the oranges, the ratio of the apples to oranges left became 1:2. What was the number of fruits Mr Tan had in the end?

2) Huiling had 160 less marbles than George. George gave 75% of his marbles to Huiling. Huiling then gave 20% of her marbles to George. If Huiling had 192 more marbles than George in the end, how many marbles did Huiling have at first?

Thanks!

[Essential]

The average age of 3 men is 21 years old. If they are of different ages and are at least 17 years old, what is the maximum possible age of the oldest person in the group?

[ms_lim]

tianzhu:

ms_lim:

Can you help with this question?


http://i48.tinypic.com/34xl0s5.jpg\">

Hi

This question has been discussed before.

Hope this helps.

Best wishes

http://farm5.staticflickr.com/4087/5038193821_f4be6c6c88_z.jpg\">

Thanks tianzhu

[MathIzzzFun]

whitety:

Hi, need help on 2 qns.


1) Mr Tan has some apples and oranges in the ratio 4: 5. After selling 170 apples and 25% of the oranges, the ratio of the apples to oranges left became 1:2. What was the number of fruits Mr Tan had in the end?


Thanks!

At first,
Apples : Oranges = 4 : 5 --> 16u : 20u
Sold, Apples : Oranges --> 170 : 5u
Left, Apples : Oranges --> 16u - 170 : 15u = 1: 2
So, 32u - 340 = 15u
1u --> 20
In the end,
Apples --> 150, Oranges --> 300, Total --> 450 apples & oranges

cheers.

[MathIzzzFun]

whitety:

Hi, need help on 2 qns.


2) Huiling had 160 less marbles than George. George gave 75% of his marbles to Huiling. Huiling then gave 20% of her marbles to George. If Huiling had 192 more marbles than George in the end, how many marbles did Huiling have at first?

Thanks!

At first,
Huiling --> 16u
George --> 16u + 160 --- 75% = 12u + 120

After George gave 75% to Huiling
Huiling --> 28u + 120 -- 20% = 5.6u + 24
George --> 4u + 40

After Huiling gave 20% to George
Huiling --> 22.4u + 96
George --> 9.6u + 64
Huiling had 192 more, so
9.6u + 64 + 192 = 22.4u + 96
4u --> 50

at first, Huiling --> 200

cheers.

[MathIzzzFun]

Essential:

The average age of 3 men is 21 years old. If they are of different ages and are at least 17 years old, what is the maximum possible age of the oldest person in the group?

Total age --> 21 x 3 = 63
63 - 17 = 46
So, total age of remaining two persons is 46
Max possible age of oldest of the two = 46-18 = 28

cheers.