Question

There are approximately 7.5x10^18 grains of sand on earth.There are approximately 7x10 ^27 atoms in an average human body.Are there more grains of sand on earth or atoms in an average human body ?How do you know?

Answer 1

There are more atoms in a human body because 7.5*10^18 is less than 7*10^27.

Answer 2

Explanation:

There are approximately 7.5 × 10¹⁸ grains of sand on earth.

There are approximately 7 × 10²⁷ atoms in an average human body.

A. There are more atoms in an average human body. When comparing the order of magnitude of each number 27 it greater than 18.

7 × 10²⁷ > 7.5 × 10¹⁸

B. Now we will calculate how many times more atoms are in a human body compared to grains of sand on earth.

`(7* 10^(27))/(7.5* 10^(18))`

=
`(7)/(7.5)* (10^(27))/(10^(18))`

≈ 1 × 10²⁷⁻¹⁸

≈ 1 × 10⁹

≈ 10⁹

There are approximately 1,000,000,000 atoms more in a human body compared to the grains of sand on earth.