SOLUTION: A tank measuring 20 cm by 12cm by 15cm was filled with some water. when 1/10 of the water in the tank was poured into a tub, the volume of water in the tub increased by 12cm^3. wha

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Question 1160280: A tank measuring 20 cm by 12cm by 15cm was filled with some water. when 1/10 of the water in the tank was poured into a tub, the volume of water in the tub increased by 12cm^3. what fraction of the tank was not filled with water at first??
a)1/30 b)29/30 c)1/10 d)9/10
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
a tank measuring 20 cm by 12 cm by 15 cm is filled with some water.
1/10 of the water in the tank is poured into a tub.
the volume in the tub increased by 12 cm^3.
what fraction of the tank was not filled with water at first?

since 12 cm^3 represents 1/10 of the water in the tank, then the amount of water in the tank had to be 10 * 12 = 120 cm^3 because 1/10 * 120 = 12 cm^3.

a full tank contains 20 * 12 * 15 = 3600 cm^3 of water.

120 / 3600 = 1/30 of the water in a full tank.
that would leave 29/30 of the volume of the tank that was not filled with water.
your solution is b) = 29/30.