An object hanging on a scale reads 24.0g when submerged in water, but 48.0g when submerged in oil (specific gravity 0.80) Find the density of the object.

Answer 1

assume Mass M for the object.

in water, 24=M-densitywater*volume
in oil, 48=M- densityoil*volume

subtract top equation from bottom.

24=densitywater*volume-densitoil*volume
volume=24/(1-.8) cm^3
volume= 120cm^3

Now, solve for M.
24=M-1*120
M=144grams

density=144/120 g/cm^3