Skip to content / Đến nội dung
ThichHocToan.com

BBB 2021 - Grade 3 - Preliminary Round Question 12

BBB · BBB 2021 - Grade 3 - Preliminary Round

Question 12

Find the value of $5+10+15+\cdots+40+45+40+\cdots+15+10+5$.
  1. 250
  2. 450
  3. 225
  4. 405