Answer:
The value is [tex]x = 3.000 * 10^9 \ grains[/tex]
Step-by-step explanation:
From the question we are told that
[tex]1m^3 = 10^6 cm^3[/tex]
And that
[tex]3000 \ grains \ of \ sand \ is \ in \ 1cm^3[/tex]
So the number of sand grain that is in [tex]1m^3[/tex] is mathematically evaluated as
[tex]x = 3000 * 10^6 \ grains[/tex]
=> [tex]x = 3.000 * 10^9 \ grains[/tex]