Final answer:
The rabbit population last year can be found by dividing this year's population by 5.
Step-by-step explanation:
To find out how many rabbits there were last year, we need to calculate the population of rabbits from last year. We know that this year's population is 700 and it is 500% of last year's population. This means that this year's population is 5 times last year's population, so we can set up the equation:
Last year's population x 5 = 700
To solve for last year's population, we divide both sides of the equation by 5:
Last year's population = 700 ÷ 5
Last year's population = 140
Therefore, there were 140 rabbits last year.