IKMC 2021 - Grades 7-8 - Set 2 - Self-study Question 20

Three villages are connected as shown. Downend to Uphill via Middleton is 1 km longer than direct; Downend to Middleton via Uphill is 5 km longer; Uphill to Middleton via Downend is 7 km longer. How long is the shortest direct path?