A= 9 × ($\frac{4}{1.3.5}$ + $\frac{4}{3.5.7}$ + $\frac{4}{5.7.9}$ + ... +$\frac{4}{25.27.29}$ )
A = 9 × ( $\frac{1}{1.3}$ - $\frac{1}{3.5}$ + $\frac{1}{3.5}$ - $\frac{1}{5.7}$ +... + $\frac{1}{25.27}$ - $\frac{1}{27.29}$ )
A= 9 × ( $\frac{1}{1.3}$ - $\frac{1}{27.29}$ )
A= 9 × ( $\frac{1}{3}$ - $\frac{1}{783}$ )
A= 9 × ( $\frac{261}{783}$ - $\frac{1}{783}$ )
A= 9 × $\frac{260}{783}$
A= $\frac{260}{87}$
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