In the bih weight of each of the 10 babies born in a hospital in a day is found to be 2.8 kgs, then the standard detion of this sample will be ?
Ans. is 'b' i.e., 0 o Standard detion measures the variation (dispersion) of an individual data from the mean. o ST tells how tightly all the values are clustered around the mean in a set of data. o High standard detion indicates that the data is dispersed away from the mean. o Low standard detion indicates that the data points tend to be very close to mean, i.e. data points are clustered close to the mean. o For example, the average height for adult men in USA is about 70 inches, and standard detion is 3 inches. Then - i) If dispersion of mean is 1 SD --> most men (about 68%) have a height within 3 inches of the mean (67-73) inches. ii) If dispersion of mean is 2 SD --> almost all men (95%) have a height within 6 inches of the mean (64 - 76) inches. iii) If dispersion is zero SD --> all men would be exactly 70 inches. o That means greater the standard detion greater will be the data spread away from standard detion. Coming back to question o Here all newborn babies has 2.8 kgs of weight. o That means there is no dispersion from mean. o So, standard detion is zero.
2.8
0
1
0.28