A welder received an order to make a 1 million liter cube-shaped tank. If he has only 5x2 meter sheets of metal that can be cut, how many metal sheets will be required for this order? (1 cubic meter = 1,000 liters) Select the correct option
A) 92
B) 60
C) 82
D) 78
E) 75
The question say:A welder received an order to make a 1 million liter cube-shaped tank. (1 cubic meter = 1,000 liters)   In other words, the tank is going to have a volume of 1000 cubic meters. That would equal 1 million liters.   A cube with a volume of 1000 cubic meters must be (10 meters) x (10 meters) x (10 meters).   The question doesn't specify whether this tank should have a closed top or an open top. (The real GMAT is good about specifying things like that.) Here, we are going to assume a closed top, only because if the top is open, we don't use enough metal --- we get an answer smaller than any of the answer choices. A closed-top cube, a full cube, has 6 sides, each of which is (10 meters) x (10 meters). That's a total surface area of 600 sq m.   The question tells us:he has only 5x2 meter sheets of metal that can be cut.   Each sheet has an area of 10 sq m. How many of these need to fill up 600 sq m? 600/110 = 60. He needs 60 sheets.   Answer =60
<result>B</result>
A welder received an order to make a 1 million liter cube-shaped tank. If he has only 5x2 meter sheets of metal that can be cut, how many metal sheets will be required for this order? (1 cubic meter = 1,000 liters)