When 50 mL of water is added, the graduated cylinder has a mass of 180 g. If a rook is added to the graduated cylinder, the water level rises to 90 mL and the total mass is now 270 g. What is the density of the rock?

2.25 (or ) g/mL

Skills needed: Density

Step-by-step explanation:

1) Briefly, let's cover what density is:

- It is

- Measures the mass per unit of volume

- In this situation the formula for density is:

---> is the final mass

---> is the initial mass

---> is the final volume

---> is the initial volume

2) In this case, we start out with a mass of 180 grams as stated in the problem, and also 50 mL of water initially.

This means that:

- is 180 g

- is 50 mL

3) Also, we end up with 270 g in mass, and 90 mL of water finally.

- is 270g

- is 90 mL

4) We can find density by substitute given the values above:

5) Our answer is 2.25 g/mL (since mass is grams (g), and volume is milliliters (mL) in the problem above).

-18

step-by-step explanation:

because mean value defines that total sum value over total number of set