Q&A - P5 Math

[pixiedust]

Thanks VC mum.


Unfortunately, I couldn't crack the problem too.
Anyone can help Superbug and me ?

Source : Rosyth School 2010 P5 SA2 Maths Paper 2 Q6
http://i53.tinypic.com/6nzerk.png\">

In addition, I am struggling with this too :
Source : Tao Nan 2010 P5 SA2 Paper 2 Q11
http://i1197.photobucket.com/albums/aa424/pixie_dust8/m2.jpg\">

[ksme]

Pixiedust and Superbug,


Rosyth School 2010 P5 SA2 Maths Paper 2 Q6

Area of triangles ABX + BXY+YDC = 1/2 of Area of rectangle ABCD = 240
Since area of BXZ = 56, the shaded area is 240-56= 184 cm2

Tao Nan 2010 P5 SA2 Paper 2 Q11

If perimeter is 56cm, BC = (56-18-18)/2=10cm
Area of ABX = 1/2 (18*10)= 90 cm2
Area of BXY = 90-42=48cm2.

Hope the above helps.

[leelk]

Question (1)

Hanis had $960 less than Lina. After Hanis gave $2400 to Lina, Lina had 3 times as much as Hanis.
a) How much did Lina have in the end?
b) How much did Hanis have at first?

Question (2)
Mr A and Ms B went shopping with a total of $300 and each bought some items. The amount Mr A spent is three times the amount he has left. The amount Ms B spent is twice the amount she has left. Given that the two friends have a total of $90 left, how much did each of them have at first?

[MathIzzzFun]

leelk:

Question (1)

Hanis had $960 less than Lina. After Hanis gave $2400 to Lina, Lina had 3 times as much as Hanis.
a) How much did Lina have in the end?
b) How much did Hanis have at first?

Question (2)
Mr A and Ms B went shopping with a total of $300 and each bought some items. The amount Mr A spent is three times the amount he has left. The amount Ms B spent is twice the amount she has left. Given that the two friends have a total of $90 left, how much did each of them have at first?

Hi
Both questions can be solved using MD too.

q1.
Initially, Hanis = 1u, Lisa = 1u + 960

After Hanis gave $2400 to Lisa,
Hanis : Lisa
= 1u - $2400 : 1u + $960 + $2400
= 1u - $2400 : 1u + $3360
= 1 : 3

Cross-multiply-

3u - $7200 = 1u + $3360
2u = $10560
1u = $5280

In the end, Lisa had 1u + $3360 = $5280 + $3360 = $8640

At first, Hanis had 1u = $ 5280

q2.

Mrs A = * * * *
Mrs B = @ @ @ (\"amount spent\" in red)

* + @ = $ 90
* * * + @ @ = $ 300 - $90 = $210

So, * = $ 210 - 2 x $90 = $30
@ = $90 - $30 = $60

At first,
Mrs A had 4 x $30 = $ 120
Mrs B had 3 x $ 60 = $ 180

cheers.

[tinasen]

Can someone help with a solution (Model methos) to solve this question pls.

Weichong and Rama collect stamps. If Rama gives Weichong 15 stamps, he will have the same number of stamps as Weichong. If Weichong gives 15 stamps, he will have 1/2 as many stamps as Rama. How many stamps does each boy have?

Answer is be Rama 105 and WeiChong 75
Here is what I attempted and came out with wrong answer
After R gives 15 to W,
Case 1: R -> []15
W -> []15

After W gives 15 to R,
Case 2: R-> [][]
W->[]
Substituting in case 2, 1U –> 15+15 -> 30
W –> 30+15 = 45
R –> 60-15 = 45

[MathIzzzFun]

tinasen:

Can someone help with a solution (Model methos) to solve this question pls.

Weichong and Rama collect stamps. If Rama gives Weichong 15 stamps, he will have the same number of stamps as Weichong. If Weichong gives 15 stamps, he will have 1/2 as many stamps as Rama. How many stamps does each boy have?

Answer is be Rama 105 and WeiChong 75
Here is what I attempted and came out with wrong answer
After R gives 15 to W,
Case 1: R -> []15
W -> []15

After W gives 15 to R,
Case 2: R-> [][]
W->[]
Substituting in case 2, 1U --> 15+15 -> 30
W --> 30+15 = 45
R --> 60-15 = 45

Hi

http://i55.tinypic.com/vfeo5.jpg\">

cheers

[ozora]

need some help in the following question http://i52.tinypic.com/15p4a2x.jpg\">

[metz]

tinasen:

Can someone help with a solution (Model methos) to solve this question pls.

Weichong and Rama collect stamps. If Rama gives Weichong 15 stamps, he will have the same number of stamps as Weichong. If Weichong gives 15 stamps, he will have 1/2 as many stamps as Rama. How many stamps does each boy have?
Answer is be Rama 105 and WeiChong 75

http://i56.tinypic.com/2uo4eaq.png\">

[MathIzzzFun]

ozora:

need some help in the following question http://i52.tinypic.com/15p4a2x.jpg\">

Hi

P + R = Q + S = 1/2 area of rectangle.

S = P + R -Q

cheers.

[tinasen]

Thank you very much Chamonix. It was schoolwork for my DS and I was struggling with it. Now I get it with your clear MD. Thanks a lot.

chamonix:

tinasen:

Can someone help with a solution (Model methos) to solve this question pls.
Weichong and Rama collect stamps. If Rama gives Weichong 15 stamps, he will have the same number of stamps as Weichong. If Weichong gives 15 stamps, he will have 1/2 as many stamps as Rama. How many stamps does each boy have?
Answer is be Rama 105 and WeiChong 75

http://i56.tinypic.com/2uo4eaq.png\">