Final answer:
We cannot be sure that x is a multiple of y given the division results in a decimal of 6.68. Other options regarding the characteristics of x and y are not determined by the division result.
Step-by-step explanation:
When the division of two integers x and y results in a decimal, such as x/y=6.68, we can derive certain properties regarding x and y. First, we can deduce that x is not a multiple of y, else the division would result in an integer. Hence, we can't be certain that x is a multiple of y (option C), as the division result is not a whole number.
Considering options A, B, and D, the resulting decimal from the division does not provide information sufficient to confirm or deny these specifics about the numbers x and y. A prime number, a perfect square, or an even number could all generate a decimal when involved in division with another integer.
To solve for y given x and the dividend 6.68, we would manipulate the equation by multiplying both sides by y and then dividing by 6.68, which results in y=x/6.68. This reveals the value of y that, when divided into x, gives the result 6.68.