HKIMO 2020 Grade 6 National Final (Heat) Set 01 Question 3

A bag contains 35 blue,29 red and 13 green balls. What is the least number to draw to guarantee 5 non-blue balls and 10 non-green balls?

Source glossary (English–Vietnamese): At least: ít nhất; How many: có bao nhiêu; Ensure: chắc chắn.