Question #31621

1 Answer
Jan 22, 2018

750,000 years

Explanation:

We can treat this question as a ratio.

#0.2"cm":100"years"#

Multiply both sides by 5 gives us:

#1cm:500"years"#

We want 15m which is 1500cm so we multiply both sides by 1500

#1500cm:750,000"years"#