Question

earth is about 4.5 billion years old, extends back to 10,000 years. it is repesented with a 10 meter timeline, what distance represents 4 billion years?

Answer 1

1 billion = 1,000,000,000 years = 10^9 years

10,000 years = 10^4 years

10^4 years are represented with a 100-meter-long timeline

10^9 years are represented with a x-meter-long timeline

10^4/100 = 10^9/x

x = 10^7 m

1 billion = 10^9 years are represented with a 10^7-meter-long timeline

4.5 billion = 4.5*10^9 years are represented with a 4.5*10^7-meter-long timeline

(4.5*10^7 - 100) meters from the start is where the written human history begins