45-The mean of 10 observations is 21. If each observation is multiplied by 4 and 5 is subtracted from each of them, then the mean will be
A. 79
B. 81
C. 84
D. 16
Answer:A
45-The mean of 10 observations is 21. If each observation is multiplied by 4 and 5 is subtracted from each of them, then the mean will be
A. 79 B. 81 C. 84 D. 16