Answer:
13.9
Step-by-step explanation:
Mean is total (sum) divided by number of values
Mean = sum/num
mean1 = 13.9 = sum1/10
sum1 = 10 x 13.9 = 139
mean2 = 13.9 = sum2/11
sum2 = 11 x 13.9 = 152.9
Total mean = total sum/total num
total sum = 139 + 152.9 = 291.9
total num = 21
291.9/21 = 13.9
