K. 470. We have cubes of two different sizes, each with edges of integer length in cm. The edges of the red cubes are 5 cm longer than the edges of the blue ones. By stacking 15 cubes on top of each other, we got a tower of height 140 cm. How long are the edges if the difference between the numbers of red and blue cubes used is as small as possible?
This problem is for grade 9 students only.
Deadline expired on 10 November 2015.