The price of a stock decreased by $.60 one week decrease $.10 the next week and decreased another $.20 the following week what is the average change in the price of the stock over the three weeks
a -270 per week
b -90 cents per week
c -87 cents per week
d -30 cents per week

Add all the numbers together then divide by the amount of numbers you added together to find the average of anything.

For this problem you add .60+.10+.20=.90 then divide .90 by 3 because you agreed 3 numbers together. .90÷3= .30 so you are subtracting 30 cents per week or (-30)

9/12 is the answer because 3/4 times 3 each is 9/12