Use a system of equations.
(x=# of small dogs, y=# of big dogs)
x+y=9 (times by -5) -5x-5y=-45
5x+8y=51
Then add the equations together and the x's cancel.
3y=6
y=2
So he walked 2 big dogs and 7 little dogs.
I believe it would be 6 due to the radius being a half of the actual circumfrence
The ? Is 11.
You add the equations to get rid of one variable, then you have 6x=24 then you divide both sides and you have x=4, then you substitute the given value of x and you are left with 5*4 - y = 9. And the solution or well possible solution is y = 11 which gives youuuuu. (x , y) = (4 , 11)
like 7,523.38
i think lol
source : https://www.bankrate.com/calculators/savings/simple-savings-calculator.aspx