Question

1/15, 1/12, 1/10, ......., to 11 terms

Answer 1

1/15, 1/12, 1/10 1/9, 1/9, 1/10, 1/12, 1/15, 1/19, 1/24, 1/30

Answer 2

$\large\sf\red{GIVEN:-}$

$\large\tt\purple{a=\frac{1}{15},}$

$\large\tt\purple{d=\frac{1}{12}-\frac{1}{15}=\frac{1}{60}}$

$\small\tt\green{The\:sum\:of\:n\:terms\:of\:an\:AP\:is\:given\:by}$

$\longrightarrow$$\large\tt\purple{Sn=\frac{n}{2}(2a+(n-1)d)}$

$\longrightarrow$$\large\tt\purple{S11=\frac{11}{2} (2( \frac{1}{15} ) + (11 - 1)( \frac{1}{60})}$

$\longrightarrow$$\large\tt\purple{S11= \frac{11}{2} ( \frac{2}{15} + \frac{1}{6} )}$

$\longrightarrow$$\large\tt\purple{S11=\frac{11}{2}(\frac{9}{30})}$

$\longrightarrow$$\large\tt\purple{S11=\frac{33}{20}}$