Question

Mean of four observations is 12. If first 2nd 3rd and 4rth observations are decreased by 1,2,3 and 4 respectively, then find the new mean.

Answer 1

Step-by-step explanation:

given that mean of the observation are = 12

then sum of observation = 12×4 = 48

if 1st, 2nd,3rd,4th observation is decreased by 1 ,2,3,4 then total sum is decreased by = 1+2+3+4 =10

so, new mean = 48 -10 /4

= 38 /4

mean =9.5