VTMO 2026 - Grade 2 - Final - SET 1 - Self-study Question 16

An has three pencil boxes. First, An moves 6 pencils from box 1 to box 2, then 4 pencils from box 2 to box 3, and finally 2 pencils from box 3 to box 1. Each box now contains exactly 10 pencils. How many pencils were originally in box 1?