Question 1
SEAMO self-study edition 2027; not an official 2027 paper. Original source years are retained. 25 questions, 90 minutes; Q1–10: 3 points, Q11–20: 4 points, Q21–25: 6 points, total 100. Original response types and all subparts are preserved. Verified is an editorial convention; source defects, necessary assumptions and unresolved mathematical uncertainty are disclosed.
Suppose $a,b,c$ are positive real numbers such that $abc(a+b+c)=100$. Find the minimum value of $(a+b)(b+c)$.
Suppose $a,b,c$ are positive real numbers such that $abc(a+b+c)=100$. Find the minimum value of $(a+b)(b+c)$.