47 is the greatest prime number less than 48.
The greatest prime number less than 200 is 199.
The greatest prime number less than 20 is 19. For there to be a difference, we'll have to have another value.
47 is the greatest prime number under 50.
The greatest prime number less than 10 is 7. To have a difference, you need at least two values.
The smallest prime number is 2 and the greatest prime number less than 100 is 97. The required product is: 2 x 97 = 194.
293
89.
29
19
19.
97