Answer:
Your question lacks some parts attached below is the complete question
Answer : 2.66
Explanation:
The expected number ( E ) can be calculated using the formula below

since we are computing the number of subjects that would prefer Linux operating system and are also rated as exceptional
The row total to be used = 53 ( row total of exceptional )
The column total to be used = 13 ( column total of Linux )
The gross total to be used = summation of row total of both exceptional and no-exceptional = 259
BACK TO THE EQUATION
E =
= 689 / 259
E = 2.6602 ≈ 2.66