Question

Find the sum of the geometric sequence. (1 point) 1, one divided by two, one divided by four, one divided by eight, one divided by sixteen

Answer 1

$sn = a(1 - {r}^{n} ) \div 1 - r \\ s5 = 1(1 - {( \frac{1}{2} )}^{5} ) \div 1 - \frac{1}{2 } \\ = 1(1 - \frac{1}{32} ) \div \frac{1 }{2} \\ = \frac{32 - 1}{32} + \frac{1}{2} \\ = \frac{31}{32} \times \frac{2}{1} \\ = \frac{31}{16}$

therefore sum of GP is 31/16