Question 13
Find the last two digits of $A=4+9+14+\cdots+(4+5\cdot98)+(4+5\cdot99)$.
HKIMO 2020 THPT (Grades 10–12 shared) National Final (Heat) Set 01 Question 13
HKIMO · HKIMO 2020 THPT (Grades 10–12 shared) National Final (Heat) Set 01
HKIMO · HKIMO 2020 THPT (Grades 10–12 shared) National Final (Heat) Set 01