The average of 22 numbers is 52. The average of first 8 numbers is 48 and that of next 11 numbers is 54. The twentieth number is 7 less than the twenty-first number and the twenty-first number is 4 more than the twenty-first number. What is the average of twentieth and twenty-two numbers?

• A. 52
• B. 52.5
• C. 53
• D. 53.5