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If $$6^{th}$$ term and $$13^{th}$$ term of a geometric progression are 24 and $$\frac{3}{16}$$ respectively, then the $$25^{th}$$ term is
let the first term is a and common ratio is r thenÂ
$$T_{6}$$= {a}$$\times{r}^{5}$$ =24Â Â Â Â Â Â equation 1Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
$$T_{13}$$= {a}$$\times{r}^{12}$$ =3\16Â Â Â equation 2
equation 1 \equation 2
24\{3\16} = 1\r^7
128Â = 1\r^7Â
2 = 1\rÂ
r = 1\2Â
put the value of r in equation 1Â
a$$\times\frac{1}{2}^{5}$$ =24Â
so we get a= 768Â so the series isÂ
768, 384,192,96,48,24,12,6,3,3\2,3\2^2,.............. so the 25^{th} term isÂ
Â
 $$\frac{3}{2^{16}}$$  answer
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