The number halfway between 18 and 60 is (18 + 60)/2 = 39.
17. A 4x4 rectangle has a perimeter of 16 units and an area of 16 square units. A 3x6 rectangle has a perimeter of 18 units and an area of 18 square units. The number 17 is halfway between 16 and 18.
(13 + 23)/2 = 18
The single number directly between those two numbers is 18.
It is 13.5 which is the value halfway between the two middle values 12 and 15.
19.5 is halfway between 18 and 21
Halfway between 18 and 28 is (18 + 28) ÷ 2 = 23.
The number halfway between 18 and 60 is (18 + 60)/2 = 39.
17. A 4x4 rectangle has a perimeter of 16 units and an area of 16 square units. A 3x6 rectangle has a perimeter of 18 units and an area of 18 square units. The number 17 is halfway between 16 and 18.
It is 20
36
It is: (18+21)/2 = 19.5
(13 + 23)/2 = 18
(5 + 13)/2 = 18/2 = 9
The single number directly between those two numbers is 18.
11.5
15