In Wren the quotient operator '/' does not round but, when the ''floor'' method is applied to the result, it rounds to the lower integer.

The sign of the remainder operator '%' matches the sign of the first operand.
import "io" for Stdin, Stdout
System.write("first number:     ")
Stdout.flush()
var a = Num.fromString(Stdin.readLine())
System.write("second number:    ")
Stdout.flush()
var b = Num.fromString(Stdin.readLine())
System.print("sum:              %(a + b)")
System.print("difference:       %(a - b)")
System.print("product:          %(a * b)")
System.print("integer quotient: %((a / b).floor)")
System.print("remainder:        %(a % b)")
System.print("exponentiation:   %(a.pow(b))")