Assertion: The sum of 5 terms of G.P. $\frac{2}{9}$ - $\frac{1}{3}$ + $\frac{1}{2}$ ..... is $\frac{55}{72}$. Reason: The sum of n terms of GP = n/2(a + r).

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KollegeApply · Accepted Answer

Assertion (A) is true, but Reason (R) is false. Explanation: The Assertion (A) is true because the given sequence is a G.P. with first term a = $\frac{2}{9}$ and common ratio r = (-3)/2. When you calculate the sum of 5 terms using the formula S_n = (a(1 - r^n))/(1 - r), you get exactly $\frac{55}{72}$. However, the Reason (R) is false because it provides a completely incorrect formula; the sum of a G.P. is never calculated using n/2(a + r).

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