The mean of a set of eight numbers is 8 and the mean of a different set of twelve numbers is m. Given that the mean if the combined set of twenty numbers is 5, calculate m.

Mean=total/the number of values = >total=mean*the number of values

the total of the first set of 8 numbers is : total=8*8=64

the total of the second set of 12 numbers is: 12m

the total of the 20 numbers is: 64+12m

the mean of the 20 number is: (64+12m) / 20=5

solve for m: 64+12m=100

12m=36

m=3