The equation for density is:
[tex]density = \frac{mass}{volume} [/tex]
To help you remember - my teacher told us to remember "We ♡ density," and the heart stands for [tex] \frac{m}{v} [/tex], or [tex]\frac{mass}{volume}[/tex]. Cheesy, but it works!
Back to the problem:
We know the mass if 49g and the volume is 7 [tex]cm^{3} [/tex], so plug these values into the equation for density:
[tex]density = \frac{mass}{volume}\\
density = \frac{49\:g}{7\:cm^{3}} \\
density = 7\:g/cm^{3}[/tex]
Answer: The density is 7 g/[tex]cm^{3} [/tex]