IKMC 2027 - Grades 7-8 - Self-study SET 6 - Thematic Batch 3 Question 2

Question 2

PQR is an equilateral triangle. The source writes “ray SR” as the bisector of $\angle PRQ$. Take T on RS so that $\angle TQR:\angle TQS=2:1$. Find $\angle STQ$.

Editorial note: The diagram identifies S on PQ and the intended bisector as ray RS from R; the Vietnamese source wording is retained.

Question illustration

$40^\circ$
$50^\circ$
$60^\circ$
$70^\circ$
$80^\circ$