when looking at fractions if the top number ( numerator) is larger then the bottom number ( denominator) the value of the fraction is greater than 1
if both the top and bottom numbers are the same, the fraction equals 1
if the top number is smaller than the bottom number then the fraction is less than 1
so with the fractions you have:
4/3 ( 4 is larger than 3 so this is greater than 1)
5/5 ( 5 = 5, so this = 1 )
4/4 ( 4=4, so this = 1)
1/2 ( 1 is smaller than 2 so this is less than 1)
1/1 ( 1 =1 so this = 1)
since 1/2 is less than 1, this is the fraction with the least value