Problem
First name
Jack Harris
School
Middleton primary school
Country
Age
11
15 digits is all about trial and error. First you match the first 2 digits so they equal 15 then add the second digit to the third so they equal 20 and so on.
If you get it wrong just try again and eventually you will get the answer. Don't give up!
My solutions are:
6 9 11 12 4 14 7