Product of a whole number:

Step-by-step explanation:
Product means multiplication.
4 out of 4 = 1
x*1= Whole number
If x equals 1, then it makes sense
1*1=1
1 is the product, the second 1 is the whole number
Unit Fraction:

Step-by-step explanation:
Unit Fraction is 1 out of something
4/4=1/1
I hope this makes sense
Have a good day!