If 12 is replaced with 3 in the following set, what will happen to the value of the range? 28, 45, 12, 34, 36, 45, 19, 20
it will increase.
it will decrease.
it will stay the same.

The range is the number of units between the smallest and largest number. organising your numbers from smallest to largest:

12, 19, 20, 28, 34, 36, 45, 45

in your case 12 is the smallest number of your set. lowering it to 3 would increase the distance between the two numbers, therefore increasing the range

hope that helps :)