5 times 20(which is your number of days) equals 100. Louis already had 25 so add both numbers together to get 125
I think it might be B
because from 9+1 = 10 we can change to 9=10-1
and 10+6=16 no need to change
then we solve the problem with the equation
16 - 9
10+6 - (10-1)
10+6-10+1
7
thats the answer