Three planks of different lengths, T, U and V are nailed together to make a frame as shown. Plank T has 3 holes which divide it into 4 equal parts. Plank U has 4 holes which divide it into 5 equal parts and Plank V has 5 holes which divide it into 6 equal parts. In the frame, the holes B, C and D are three corners of an equilateral triangle. Plank T is 216 cm long. What is the total length of Plank T, Plank U and Plank V?
Length of Plank T = 216 cm

Length of each interval of Plank T
= 216 ÷ 4
= 54 cm

Length of 2 intervals of Plank T
= 2 x 54
= 108 cm

Length of each interval of Plank U 
= 108 ÷ 3
= 36 cm

Length of Plank U
= 5 x 36
= 180 cm

Length of each interval of Plank V
= 108 ÷ 4
= 27 cm

Length of Plank V
= 6 x 27
= 162 cm

Total length of Plank T, Plank U and Plank V
= 216 + 180 + 162
= 558 cm

Answer(s): 558 cm