Answer: 1,350 hats
Step-by-step explanation: First, it's important to understand that 50% is equivalent to the fraction 1/2.
So, the next year that hat store will sell 1/2 more hats.
First, we need to divide 900 by 2 which gives us 450.
Now, we simply add 450 to to the number of hats the store sold the first year.
450 + 900 = 1,350
This means that the hat store will sell 1,350 hats the next year.