if the arithmetic mean of four numbers is 20 and the arithmetic mean of other six numbers is 10 then,find the arithmetic mean of all the numbers taken as one group
Sum = Average (Arithmetic Mean) * No of observation
Sum_1 = 20*4 = 80
Sum_2 = 10*6 = 60
Sum = 80 + 60 = 140
Average = 140/10 = 14