X - John's shoe size
Two people in the family wear shoe size 6, but John's shoe size is not 6.
The shoe sizes in the family:
6, 6, x
The range is the difference between the highest and the lowest value. The range is 4.
There are two possibilities:
1. John's shoe size is the biggest:
However, his shoe size is not 10, so it's impossible.
2. John's shoe size is the smallest.
John's shoe size is 2.
Two people in the family wear shoe size 6, but John's shoe size is not 6.
The shoe sizes in the family:
6, 6, x
The range is the difference between the highest and the lowest value. The range is 4.
There are two possibilities:
1. John's shoe size is the biggest:
However, his shoe size is not 10, so it's impossible.
2. John's shoe size is the smallest.
John's shoe size is 2.