If the $7^{ ext {th }}$ term of a H.P is 8 and the $8^{ ext {th }}$ term is 7 , then its $15^{ ex

Question

If the $7^{	ext {th }}$ term of a H.P is 8 and the $8^{	ext {th }}$ term is 7 , then its $15^{	ext {th }}$ term is

Professor PC Thomas Classes · Answer

For HP, $\mathrm{T}_7=8, \mathrm{~T}_8=7$. In the corresponding AP $\mathrm{a}+6 \mathrm{~d}=\frac{1}{8}$ and $\mathrm{a}+7 \mathrm{~d}=\frac{1}{7}$. Solve for a and d .