SOLUTION: A tank measuring 20 cm by 12 cm by 15 cm was filled with some water. The ratio of the volume of water in the tank to the volume of water in a tub was 5:2. When 1/10 of the water in

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: A tank measuring 20 cm by 12 cm by 15 cm was filled with some water. The ratio of the volume of water in the tank to the volume of water in a tub was 5:2. When 1/10 of the water in      Log On


   

Question 540822: A tank measuring 20 cm by 12 cm by 15 cm was filled with some water. The ratio of the volume of water in the tank to the volume of water in a tub was 5:2. When 1/10 of the water in the tank was poured into the tub, the volume of water in the tub increased by 12 cm^3. What fraction of the tank was not filled with water in the beginning?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
A tank measuring 20 cm by 12 cm by 15 cm was filled with some water.
The ratio of the volume of water in the tank to the volume of water in a tub was 5:2.
When 1/10 of the water in the tank was poured into the tub, the volume of water in the tub increased by 12 cm^3.
What fraction of the tank was not filled with water in the beginning?
:
Find the vol of the tank:
20*12*15 = 3600 cu/cm
:
Let x = amt of water in the tank originally
:
"When 1/10 of the water in the tank was poured into the tub, the volume of water in the tub increased by 12 cm^3."
.1x = 12 cu/cm
x = 120 cu/cm in the tank originally
:
I don't think it matters how much was in the tub, we just want to know it increased by 12 cu/cm, which represented 1/10 of the amt in the tank.
:
"What fraction of the tank was not filled with water in the beginning?"
%283600-120%29%2F3600 = 87%2F90 was not filled with water