Answer:
The rock weighs 3 pounds more on Earth than on Mar
Step-by-step explanation:
Given that the weight of an object in Mars is 2/5 its weight on earth.
![M=(2)/(5)E](https://img.qammunity.org/2023/formulas/mathematics/college/vlryrfyxgoukig4j5q4axokhtohpgp9is9.png)
If a rock weighs 5 pounds on Earth;
![E=5\text{ lb}](https://img.qammunity.org/2023/formulas/mathematics/college/nhmm7v5psnfa1fka7n607au2olf76618yk.png)
its weight on mars will be;
![\begin{gathered} M=(2)/(5)(5\text{ lb)} \\ M=2\text{ lb} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/nq02ecmto0hpis1fsqukpyxi7k18ru7xet.png)
The difference between their ages is;
![\begin{gathered} =E-M \\ =5lb-2lb \\ =3\text{ lb} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/4dzhtriw5rkle4720xa6skg5vei5xbg9nm.png)
Therefore, the rock weighs 3 pounds more on Earth than on Mars.