Answer
200 nickels are in 1kg of nickels.
Work Step by Step
Use ratios and cross multiplication to find the number of nickels. Ratios must use the same units of measure, so note that 1kg=1000g.
$\frac{1\ nickel}{5g}=\frac{x\ nickels}{1000g}$
$(5)(x)=(1)(1000)$
$5x\div5=1000\div5$
$x=200$
