(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Hey guys.

Look at this one, I have a ball with density p1 and radius R. Inside the ball they dig another ball with radius R/2 and fill it up with material that has density p2. My question is, why does the mass "m" equals to what they wrote in the answer (marked with red)? why do I need to subtract the densitys in order to find the new mass?

10x.

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Mass of a ball with different density

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