If your front lawn is 22.0 feet wide and 20.0 feet long, and each square foot of lawn accumulates 1350 new snow flakes every minute, how much snow (in kilograms) accumulates on your lawn per hour? assume an average snow flake has a mass of 1.90 mg.

The first thing we must do for this case is find the grass area:
 
 We are now looking for the quantity of snowflakes:
 
 We consider the following conversion:
 
 Therefore, after 1 hour we have:
 
 We consider the following conversion:
 
 Therefore, as the mass is 1.90 mg then:
 
 
 67.716 Kg of snow accumulates on your lawn per hour