Answer:
8
Step-by-step explanation:
Consider that the way to calculate the mean is the sum total of the values in the series, divided by the number of the series so Mean = SumX / N
We need to calculate the value of the first four numbers and last 3 numbers.
For the first set
5 = X/4 Therefore 5*4 = X so X is 20
For the second set
12 = Y/3 therefore 12*3 = Y so Y is 36
Add them together to get the sum of the full set (remember the calculation for the mean)
36 + 20 = 56
Mean = Sum X (which is 56) / N (which is 7)
So the answer is 56/7 = 8
