#8.99*10^9# seconds is how many years?

1 Answer
Sep 7, 2016

Answer:

#"285 years"#

Explanation:

Your strategy here will be to use a series of conversion factors to take you from

  • seconds to minutes

#"1 minute " = " 60s seconds"#

  • minutes to hours

#"1 hour " = " 60 minutes"#

  • hours to days

#"1 day " = " 24 hours"#

  • days to years

#"1 year " = " 365.25 days"#

The last conversion factor doesn't use a whole number because once every #4# years we have what is called a leap year, which means that instead of #365# days, the number of days we have in a regular year, we get #366# days.

So, use the conversion factors to find

#8.99 * 10^9 color(red)(cancel(color(black)("s"))) * (1color(red)(cancel(color(black)("min"))))/(60color(red)(cancel(color(black)("s")))) * (1color(red)(cancel(color(black)("hr"))))/(60color(red)(cancel(color(black)("min")))) * (1 color(red)(cancel(color(black)("day"))))/(24color(red)(cancel(color(black)("hr")))) * "1 year"/(365.25color(red)(cancel(color(black)("days"))))#

#=2.85 * 10^2"years" = "285 years"#

The answer is rounded to three sig figs, the number of sig figs you have for #8.99 * 10^9# seconds.