Astronomy question about comets

Question

I am stuck on this one question on my science homework, and I would like to know how to answer it so I can be ready for a quiz, too. Please help.

 

Suppose a comet passes the sun every 57 years, and it loses 8000 m3 of ice and rock each time. If the last time this comet was seen was in 1965, and it had a mass of 400,000 m3, in what year will the comet have passed the sun 3 more times, and how massive would it be then?

Answer 1

If the comet passes three more times, and it takes 57 years to make a single pass, then that means the equation we need is:

57 * 3 = 171

So it will take 171 years to complete three more passes.

If the last pass was 1965, then we add the time we just calculated to the original date:

1965 + 171 = 2136

So it will be 2136 after three more passes around the Sun.

 

If the comet loses 8000 m³ every pass, and it passes three times, then the amount lost is the same as:

8000 * 3 = 24,000

If the comet's mass in 1965 was 400,000 and it loses the 24k total after that third pass, then the equation looks like:

400,000 - 24,000 = 376,000.

And so the comet's mass will be 376,000 m³.