After Valen had stacked up 16 chairs in the parade square after a party, he noticed 3 things. Firstly, each of the chairs was stacked the same height above the other. Secondly, the foot of the ninth chair was 72.8 cm above that of the first. Thirdly, the chairs reached a height of 228.4 cm. What is the height of each chair?
Number of chairs that contributed to the height of 72.8 cm above the first chair
= 9 - 1
= 8

Height increase with each additional stacked chair
= 72.8 ÷ 8
= 9.1 cm

Number of chairs stacked on top of the first chair
= 16 - 1
= 15

Height increase of 15 additional stacked chairs
= 15 x 9.1
= 136.5 cm

Height of one chair
= 228.4 - 136.5
= 91.9 cm

Answer(s): 91.9 cm