Unskilled: A base of a triangular tank has a length of 14cm with a perpendicular width of 10cm and it is 3/4 full. When I dropped a rock with a volume of 460 cm3 inside the tank, the water level rose to the top and 40ml spilt out. What was the depth of the water before the rock was put in?
Great! A proper question.
Very first you need to know that an internal volume of 1cm
3 has a capacity of 1ml. This is handy for you to always know.
1) Let x be the height of the water displaced by the rock. At this this stage you can 'pretend' that the water doesn't flow over the top.
Set up an equation and solve for x
2) Now I need to find how much of this 'height' actually flowed over the top.
Let the overflow 'height' be y
Set up an equation and solve for y
3) now the tank was originally 3/4 full
so x-y = the other 1/4 of the tank.
this might be easier to understand as you do the question.
Draw the tank, diagrams always make it easier to think straight. 4) You now know what 1/4 of the tank is so your can find 3/4 of the tank easily. And that is the answer.
Once you get the answer you should check that it really works.
Have a go your self, if you get stuck I'll help more.
If you get the answer, tell everyone on the forum what it is.
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