Please help me.. :'( Its Solid Mensuration/ Geometry..
A Rectangular tank is made of aluminium sheet 5 in. thick. The external dimension of the tank are 5 ft. long, 10 ft. wide, 12 ft. deep. Find the weight of oil that will fill the tank to full and find the weight of the tank when full of oil. (Oil weighs 52 lbs/cu.ft. and aluminium is 167 lbs/cu.ft.)

Question

Please help me.. :'( Its Solid Mensuration/ Geometry..
A Rectangular tank is made of aluminium sheet 5 in. thick. The external dimension of the tank are 5 ft. long, 10 ft. wide, 12 ft. deep. Find the weight of oil that will fill the tank to full and find the weight of the tank when full of oil. (Oil weighs 52 lbs/cu.ft. and aluminium is 167 lbs/cu.ft.)

imqwerty · Answer

okay so we are gonna fill oil in the tank to the top
and then we gotta tell what will the weight of tank
|dw:1451822457787:dw| 
notice that the oil is gonna go inside the tank and volume of oil will be equal to inside volume of tank

by inside volume of tank i mean that we have to subtract the thickness from the outer dimensions to get the inner dimensions to get the inner volume