40
50 is exactly halfway between 40 and 60.
The number halfway between 18 and 60 is (18 + 60)/2 = 39.
60
65
It is: 70
(30+60)/2 = 45
59.5
It is: 45
75
60(40+80)/2 = 60
80 It is 20 more than 60 and 20 less than 100 To find a halfway point (which is also the average), add the numbers together and divide by 2.60 70 *80* 90 100As you can see, the answer is 80.
It is: (63+57)/2 = 60