Answer:
The required division problem he must solve is:

Step-by-step explanation:
Consider the provided information.
Martin chose two of the cards below. When he found the quotient of the numbers, his answer was -16/9.
As we know that the quotient of the number is a negative number.
Therefore, the sign of both numbers must be different,
Thus we can concluded he must select
as one of the card, so that product is a negative number.
Let the selected card be x.

Hence, the two cards should be
and 
The required division problem he must solve is:
