How do you write five is to one as 20 is to four as a proportion in fractional notation

To write "five is to one as 20 is to four" as a proportion in fractional notation, we first need to calculate the ratio of the two sets of numbers:

5:1 = 5/1
20:4 = 20/4

Now, we can write the proportion in fractional notation as:

5/1 = 20/4

Therefore, "five is to one as 20 is to four" can be written as 5/1 = 20/4.