Ruby program to calculate interest

Following program shows you how to calculate interest.
In this program we get investment, interest rate and time from user and calculate interest using following formula
Interest = investment X interestRate X time / 100

 puts "Enter investment:"
 investment = Integer(gets.chomp)
 puts "Enter interest rate:"
 interestRate = Integer(gets.chomp)
 puts "Enter number of years:"
 time = Integer(gets.chomp)
 interest = investment * interestRate * time / 100
 puts "Interest amount is: #{interest}"

Output:

Enter investment:
100000
Enter interest rate:
24
Enter number of years:
2
Interest amount is: 48000