Q&A - PSLE Math

[Ender]

Hi, ps help. Many tks and God Bless:)


1) 2 identical boxes, Box A and Box B, contained some sand. When 2.4kg of sand was moved from Box B to Box A, the mass of Box B was four times the mass of Box A. If another 0.8kg of sand was moved from Box B to Box A, the mass of Box B would be 3 times the mass of Box A. Find the mass of Box B at first.

[SOS mum]

Hi, ps help. Many tks and God Bless:)


1) 2 identical boxes, Box A and Box B, contained some sand. When 2.4kg of sand was moved from Box B to Box A, the mass of Box B was four times the mass of Box A. If another 0.8kg of sand was moved from Box B to Box A, the mass of Box B would be 3 times the mass of Box A. Find the mass of Box B at first.

[Ender]

Hi, ps help. Many tks and God Bless:)
2) There are 2 identical containers, Containers A and B. Container A is filled with cement and its total mass is 22.3kg. Container B is filled with water and its total mass is 11.9kg. If 1/3 of the cement in Container A is poured into Container B, they would weigh the same. Find the mass of the empty container in grams.

In order for both containers to weigh the same, amount of weight to transfer = (22.3-11.9)/2 = 5.2kg

1/3 of cement weighs 5.2kg
3/3 cement weigh =5.2 X 3 = 15.6kg

Weight of container = 22.3 - 15.6 = 6.7kg = > 6700g

[belnanna]

Someone Please help~ thanks in advance... Can anyone help to explain the solution please...

[Ender]

Someone Please help~ thanks in advance... Can anyone help to explain the solution please...

You can imgaine figure A is made up of 2 cuboids on top of each other.
The top cuboid = 16 X 10 X 2 = 320cc
The bottom cuboid = 20 X 10 X 2 = 400cc

a) Total volume of Figure A = 320+400=720 cc

b) For 5616 cc of water, number of full tank = 5616/720 = 7.8
There'll will be 7 full tanks, water contain in the 7 tanks = 7 * 720 = 5040cc

Leftover water to filled the top last tank, (i.e 8th tank) = 5616-5040 = 576cc
Looking at figure A, out of 576cc, 400cc is used to filled the bottom cubiod, leaving 176cc for the top cuboid.

Base area of top cuboid= 16X10= 160cm2
height of water level for the top cuboid = 176/160 = 1.1cm

Total height of water level, = Height of the 7 tanks (7 X 4) + height of lower cuboid of figure A(2cm) + 1.1cm
=7 X 4 + 2 + 1.1 = 31.1cm

[belnanna]

Someone Please help~ thanks in advance... Can anyone help to explain the solution please...

You can imgaine figure A is made up of 2 cuboids on top of each other.
The top cuboid = 16 X 10 X 2 = 320cc
The bottom cuboid = 20 X 10 X 2 = 400cc

a) Total volume of Figure A = 320+400=720 cc

b) For 5616 cc of water, number of full tank = 5616/720 = 7.8
There'll will be 7 full tanks, water contain in the 7 tanks = 7 * 720 = 5040cc

Leftover water to filled the top last tank, (i.e 8th tank) = 5616-5040 = 576cc
Looking at figure A, out of 576cc, 400cc is used to filled the bottom cubiod, leaving 176cc for the top cuboid.


Base area of top cuboid= 16X10= 160cm2
height of water level for the top cuboid = 176/160 = 1.1cm

Total height of water level, = Height of the 7 tanks (7 X 4) + height of lower cuboid of figure A(2cm) + 1.1cm
=7 X 4 + 2 + 1.1 = 31.1cm

Thanks so much Ender~

[Swift Formula]

a) Volume = Base x Height

b) 5616 / AnsA = AnsB with remainder
AnsB x 4cm = Height
Water Level = Height + Height of remainder
To find height of remainder please go calculate base area of Figure A and until what height the base area will change.

I'm Sorry.. Please explain more.. Still dont understand your meaning of ""until what height the base area will change"" Thanks in advance

Sorry was very buzy. Injure my foot
Thank you Ender.
anna

[Wgh2005]

Hi, can someone help me with the below question. Thank you!

[Swift Formula]

Hi, can someone help me with the below question. Thank you!

Draw model. Or list out like me.

A = 1 unit
B = 2 units
C = 6 units
D = 8 units

C/Total = ?

[Dragon Flame]

Please Help. Tks in adv !