Tutor MathsGuru: Ask me for your burning Maths questions!

[Dharma]

kancheongmum:

Dharma:

[quote=\"Almighty\"]Hi all,

Can anyone help me on this probelm..Is the answer 126cm2

http://www.postimage.org/image.php?v=aV6VnHi

Correct.

Hi Dharma how do you get the answer 126 cm2. Looking at the fig I think is 120 cm2. Pls adv if I am wrong[/quote]
Hi kancheongmum,

If we shift the shaded quadrant the top right hand corner of the rectangle to the bottom left handed corner so that it fits into the unshaded quadrant there.

We have a figure which consist of an unshaded square(top right hand) within rectangle ABCD.

Now draw a vertical line downwards from the top left hand corner of the unshaded square. So sorry I'm unable to draw it out cause I replying using my I-phone.

We do not know the of the square, so we call it 1u

Shaded area
= 10 x ( 5 + 1u) + 5 x 1u
= 50 + 15u

15u + 50 = 110
15u = 60
1u = 4

Area of square = 4 x 4 = 16
Area of Rectangle ABCD
= Shaded area + Area of square
= 110cm2 + 16cm2
= 126cm2

[Almighty]

Dharma:

kancheongmum:

[quote=\"Dharma\"]
Correct.

Hi Dharma how do you get the answer 126 cm2. Looking at the fig I think is 120 cm2. Pls adv if I am wrong

[/quote]Thanks Dharma and others!!

[CJM]

hi all, pls help with this question :


A large water tank has two inlet pipes ( a large one and a small one ) and one outlet pipe. it takes 3 hours to fill the tank with the large inlet pipe. On the other hand, it takes 4 hours to fill the tank with the small inlet pipe. The outlet pipe allows the full tank to be emptied in 7 hours.

What fraction of the tank ( initially empty ) will be filled in 2.27 hours if all three pipes are in operation? Give your answer to two decimal places.

[starlight1968sg]

CJM:

hi all, pls help with this question :


A large water tank has two inlet pipes ( a large one and a small one ) and one outlet pipe. it takes 3 hours to fill the tank with the large inlet pipe. On the other hand, it takes 4 hours to fill the tank with the small inlet pipe. The outlet pipe allows the full tank to be emptied in 7 hours.

What fraction of the tank ( initially empty ) will be filled in 2.27 hours if all three pipes are in operation? Give your answer to two decimal places.

Is the ans in fraction or decimal corrected to 2 dec pl?
What is the ans?

[MOE Hater]

CJM:

hi all, pls help with this question :


A large water tank has two inlet pipes ( a large one and a small one ) and one outlet pipe. it takes 3 hours to fill the tank with the large inlet pipe. On the other hand, it takes 4 hours to fill the tank with the small inlet pipe. The outlet pipe allows the full tank to be emptied in 7 hours.

What fraction of the tank ( initially empty ) will be filled in 2.27 hours if all three pipes are in operation? Give your answer to two decimal places.

I don't understand. You asked for a fraction then said to give the answer to 2 decimal places

[kancheongmum]

Almighty:

Dharma:

[quote=\"kancheongmum\"]Hi Dharma how do you get the answer 126 cm2. Looking at the fig I think is 120 cm2. Pls adv if I am wrong

Thanks Dharma and others!!

[/quote]Hi Dharma and Maths6a, sorry I realised my mistake after posting got the same working as Dharma.
thanks very much Dharma and tianzhu your solutions on all question are very helpful.

[kancheongmum]

tianzhu:

Hi clblinym


You're welcome.

Best wishes

Hi tianzhu really like your graphics in your answers. I hope you don't mind explaining to me on the solution of sheep eating grass again. I don't quite get it thank very much.

[maths6a]

MOE Hater:

CJM:

hi all, pls help with this question :


A large water tank has two inlet pipes ( a large one and a small one ) and one outlet pipe. it takes 3 hours to fill the tank with the large inlet pipe. On the other hand, it takes 4 hours to fill the tank with the small inlet pipe. The outlet pipe allows the full tank to be emptied in 7 hours.

What fraction of the tank ( initially empty ) will be filled in 2.27 hours if all three pipes are in operation? Give your answer to two decimal places.

I don't understand. You asked for a fraction then said to give the answer to 2 decimal places

Sorry I worked answer to be 0.999 so rounded up will be 1.00 which is like whole tank is filled???

[MOE Hater]

maths6a:

MOE Hater:

[quote=\"CJM\"]hi all, pls help with this question :


A large water tank has two inlet pipes ( a large one and a small one ) and one outlet pipe. it takes 3 hours to fill the tank with the large inlet pipe. On the other hand, it takes 4 hours to fill the tank with the small inlet pipe. The outlet pipe allows the full tank to be emptied in 7 hours.

What fraction of the tank ( initially empty ) will be filled in 2.27 hours if all three pipes are in operation? Give your answer to two decimal places.

I don't understand. You asked for a fraction then said to give the answer to 2 decimal places

Sorry I worked answer to be 0.999 so rounded up will be 1.00 which is like whole tank is filled???[/quote]Me too! Fraction is 8399/8400

[starlight1968sg]

My ans is almost 1 tank, after rounding off.