Answer:
subtract 1 then divide 2
Step-by-step explanation:
One year has 12 months therefore...
18/12 = 1 6/12 = 1 1/2
1 1/2 is equivalent to 1.5
True
Looks like 14.4 because you have to add them all together and divide by the total numbers
(20+22+10+5+15)/ 5
