Tuesday, April 21, 2015

String around the rod


The 'string around the rod' test question was posed to students sitting exams in 16 countries around the world by the International Association for the Evaluation of Educational Achievement.

1 comment:

Taposik said...

Use Pythagorean Theorem. Cut the string in 4 pieces. Each piece climbs a height of 3 cm and circles 4 cm. So each piece is of the length 5 cm (3^2 + 4^2 = 5^2). Four such pieces makes it 20 cm.