If the price of avocados increases by 20% for four consecutive months, then the price of avocados increased by 80% over the four-month period.What percentage did the avocados increase by?

Answer 1

try a specific example

Let the price start at $1,

end of 1 month it's now $1.20

2nd month it's 1.2(1.2) = $1.44

3rd month it's 1.2^3 = $1.73

4th month it's 1.2^4 = $2.07

that's a 107% increase over 4 months

1.07($1) = $1.07+$1 = $2.07

multiply 4 times 20% per month doesn't tell you the percentage change of the 4 month period

the 20% is compounded monthly, making the total % change larger than 80%