Primary Maths Challenge

[WP]

Checking it again, there's already some oil in it (filling the pipe), and now you're adding 100 litres, so the volume of the pipe doesn't come into it.

[Milla]

oh dear again. this all comes down to my old friend, the one I beat my children with, of not reading the whole thing properly!

[Nathair]

cor, well done! I don't think we do these - and wouldn't if did, if you get what I mean. Very difficult!!
I looked at one, the paper from November 2008, and there was one which I couldn't work out at all: question 25, the water in the tank one:
http://m-a.org.uk/resources/Paper_Feb2008.pdf
if anyone can explain it in words of one syllable, I'd be grateful!
Congrats again.

Ok, I asked my OH, and I think I've got it....
Tank 1 and tank 2 are linked
So the surface area is (80 x 80) + (60 x 60) = 10,000cm2

You add 100l of oil
1ml = 1cm3, so 1l = 1000cm3, so 100l = 100,000cm3

100,000cm3 / 10,000cm2 = 10cm
.....oil....... ........area... .....depth...

The oil inboth tanks will rise by 10 cm, the fact that one is smaller than the other makes no difference as the oil will settle at the same depth in both tanks.

[Nathair]

Darn , beaten to it in the time it took DH to explain it to me

[Milla]

oh dear, Nathair, but I bet it felt good being clever!