Answer:
mean of other sixteen numbers is 40
Step-by-step explanation:
let the total of 20 numbers be x
x/20 = 42
20×x/20 =42×20
x=840
let the total of four numbers be y
y/4=50
4×y/4 = 50×4
y=200
so as to get the difference of x - y
=840-200
=640
the average of sixteen numbers
=640/16
=40
therefore the mean of sixteen numbers is 40