Harsha made a wind chime using a frame and metal rods. She punched 8 holes in the frame, each 2 cm a

Question

Harsha made a wind chime using a frame and metal rods. She punched 8 holes in the frame, each 2 cm apart, and then hung 6 metal rods from the frame, as shown in the figure below. The ends of the metal rods are aligned over a line, shown by the dotted line in the figure.\ If all of the rods are straight and not swaying, then what is the length of $\operatorname{Rod} P$ ?\

Professor PC Thomas Classes · Answer

(d): Let the first term be $a=6 \mathrm{~cm}$.\ $	herefore \quad a_{8}=29 \mathrm{~cm}$\ $	herefore \quad a+7 d=29$\ $\Rightarrow \quad 6+7 d=29$\ $\Rightarrow 7 d=23$\ $\Rightarrow d=\frac{23}{7}$\ $	herefore \quad a_{4}=a+3 d=6+\frac{3 	imes 23}{7}=\frac{42+69}{7}=\frac{111}{7} \mathrm{~cm}$\ $	herefore \quad$ Length of rod ' $P$ ' $=\frac{111}{7} \mathrm{~cm}$\