Final answer:
The product of 18 negative numbers and 20 positive numbers is a positive number.
Step-by-step explanation:
The product of 18 negative numbers and 20 positive numbers can be determined by considering the rules of multiplication with signed numbers. When two negative numbers multiply, the answer has a positive sign. So, multiplying 18 negative numbers will result in a positive number. And when two positive numbers multiply, the answer is also positive.
Therefore, multiplying 20 positive numbers will also result in a positive number. When we multiply a positive number by a positive number, the product is positive. So, the overall product of 18 negative numbers and 20 positive numbers is a positive number.