–1 and 0 –1 and +1 0 and 1 None of these Answer 2. –1 and +1
If N = 10, ΣX = 60, ΣX2 = 1000, then standard deviation will be
8 12 6 100 Answer 1. 8
The mean of 15 numbers is 15. If the two numbers 16 and 14 are excluded, then the mean of the remaining numbers will be :
15 10 25 12 Answer 1. 15
Mean wage earning of workers of an organisation is Rs. 29.47 and total wages paid is Rs. 560. The number of workers in the organisation will be
20 19 21 22 Answer 2. 19