24815

At first I did this:

46 divided by 15=3.0666666
44 divided by 14=3.1428571
43 divided by 14=3.0714285
42 divided by 14=3
41 divided by 14=3.1538461
39 divided by 13=3.25
38 divided by 12=3.1666666
36 divided by 12=3
29 divided by 12=3.2222222
28 divided by 9=3.1111111
27 divided by 9=3
26 divided by 9=3.25
25 divided by 8=3.125

The last division sum is the correct answer. At first I did 46 divided by 15=3.06666666, so I knew the two numbers had to be lower. When I got down to 25, I knew that the dividing number had to be reasonable. So I tried 8. Hey presto! I got the answer right. Last algorithm - 25 divided by 8= 3.125