The average of 9 results is 45 . If the average of the first four results is 44 and that of the last four is 47 , the fifth no. is :
Answer & explanation
Correct answer: option 3
Average of 9 results = 45
Sum of these 9 results = 405
Sum of first four numbers = 44 × 4 = 176
Sum of last four numbers = 47 × 4 = 188
∴ 5th number = Sum of all numbers - ( Sum of first four numbers + Sum of last four numbers )
5th number = 405 - ( 176 + 188 ) = 41