The percentage or fraction of geological timescale that is represented by the recorded history of human kind.

Question

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Answer 1

Question

Chapter 1, Problem 1GST

To determine

To calculate: The percentage or fraction of geological timescale that is represented by the recorded history of human kind.

Expert Solution & Answer

Answer to Problem 1GST

The percentage of geological timescale represented by the recorded history of human kind is 0.000100 .

Explanation of Solution

Given info:

The length of recorded history for humankind is about 5000 years and the age of the Earth is 4.5 billion years that can be approximated as 5 billion years .

We know that 1 billion =109 years , therefore 5 billion years =5×109 years .

The expression for calculating the fraction of geological timescale represented by the recorded human history,

Fraction of timescale denoted by recorded human history =Length of recorded human historyAge of the Earth

Substitute 5000 years for the length of recorded human history and 5×109 years for the age of Earth in the above expression.

Fraction of timescale denoted by recorded human history =5000 years5×109 years=0.000001

The expression for calculating the percentage of the fraction denoted by recorded human history, Percentage of the fraction of timescale denoted by recorded human history =Fraction of human history×100

Substitute 0.000001 for the fraction of human history in the above expression.

Percentage of the fraction of timescale denoted by recorded human history =0.000001×100=0.000100

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