You would expect the answer to be 19 & 1 (giving just 19).
However 21 & -1 give you a product of -21, and 23 & -3 gives -69. So, if you allow negative numbers, there is no limit.
Product = multiply.
The numbers are: -6 and 3
The numbers are 120 and 200
529.
12 x 11 = 132. The numbers on the outside add up to the one in the middle.
9 and 11
The sum of the five smallest prime numbers is 18.
If you simply add numbers the answer is the sum of those numbers.
Product = multiply.
The numbers are: -6 and 3
45
the two numbers are 50.54657341 and -8.546573405 That was a good try. The two numbers do add up to 42, but unfortunately the product of a positive and a negative is negative, so that they multiply to give -432 rather than 432. The correct answer is 18 and 24
116
The numbers are 120 and 200
529.
You add up all the numbers that they give you. It makes no differenceif some of the numbers happen to be equal to others.
"Product" means to multiply. "Sum" means to add.