Answer
800 Nickels
Work Step by Step
Total weight of Nickels = 4 Kg = 4000 g
Weight of one Nickel = 5 g.
To find out the total number of nickels, we divide total weight by the weight of one nickel.
Number of nickels = $\frac{Total\ Weight\ of\ nickels}{weight\ of\ one\ nickel}$ = $\frac{4000}{5}$ = 800.
There are 800 nickels.