SOLUTION: Hi I am having trouble with these two maths questions. It would be great if you could send me the working out!! Two tanks contain equal amounts of water. They are connected by

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Question 827135: Hi I am having trouble with these two maths questions. It would be great if you could send me the working out!!
Two tanks contain equal amounts of water. They are connected by a pipe and 3000 liters of water is pumped from one tank to the other. One tank then contains 6 times as much as water as the other. How many liters of water did each tank contain originally?

A 120 page book has p lines to a page. If the number of lines were reduced by 3 on each page the number of pages would need to be increased by 20 to give the same amount of writing space. How many lines were there on the page originally?
Thanks
Found 2 solutions by josgarithmetic, JBarnum:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Let p = amount of water initially in each tank.

3000 gallons pumped from one tank to the other.
Say, left tank has p+3000 gallons; right tank has p-3000 gallons.
Understand that p%2B3000%3Ep-3000.

Left tank has six times the water that right tank has:
highlight%28p%2B3000=6%28p-3000%29%29;
If you understand all that, then you are now fine. Solve for p.

Answer by JBarnum(2146) About Me  (Show Source):
You can put this solution on YOUR website!
these look to be set up alor like age word problems more than quadratics.
tank A and tank B
"Two tanks contain equal amounts of water." A=B
so if we take 3000 liters from A and give it to B they are now saying that B has 6 times more water than A
its the same as saying A-3000 is now 1/6 of B%2B3000
the equation will look like:
A-3000=%28B%2B3000%29%2F6
now if A=B sub out A with B
B-3000=%28B%2B3000%29%2F6
get rid of fraction by multiplying by 6
6B-18000=B%2B3000
subtract a B and add 18000 to both sides
5B=21000
divide by 5
B=4200
so if A=B
then A=highlight%284200%29
now check
if 3000 gets taken from A and given to B it should look like this
4200-3000=1200=the new value for A and 4200%2B3000=7200= the new value for B
B should be 6 times greater lets see
7200%2F1200=6
this is correct
whoops forgot the second equation....

1 page has P amount of lines
there is 120 pages in the book so 120P=total amount of lines in the book
so if P is reduced by 3 the book would need 20 more pages to be equal to original set up.
120P=140%28P-3%29 I added the 20 pages to the original 120 pages and that total like the first part gets multiplied by how many lines there are per page.
(total pages times lines per page)=(total pages times lines per page)
distribute the 140
120P=140P-420
subtract 120P and add 420 to both sides
420=20P
divide by 20
highlight%2821%29=P
so this means that originally there were 21 lines per page
lets check to make sure
120%2821%29=2520lines in book
140%2821-3%29=2520lines in book
this is correct