trying wait a minute
\frac{4}{19}+\frac{44}{19^{2}}+\frac{444}{19^{3}}+......infinity
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15 Answers
prateek punj
·2009-04-29 09:39:14
options....
a)16/35
b)38/81
c)36/171
d)none....
i got (b)...but the ans is (c)...given.....
Celestine preetham
·2009-04-29 09:46:33
gvn =4 (1/19 + 11/192....)
= 4(1+10/19+100/192....)(1/19 +1/192...)
=4X19/9/18 =38/81
me too gettin b !!!!!!!
prateek punj
·2009-04-29 09:47:19
first take 4 common....then multiply & divide by 9....then write...
9=10-1
99=102-1
999=103-1...
then forming two g.p.
\frac{4}{9}\left[\left(\frac{10}{19}+\frac{10^{2}}{19^{2}}+... \right)-\left(\frac{1}{19}+\frac{1}{19^{2}}+..... \right) \right]
gordo
·2009-04-29 09:50:30
write down the individual term...resolve into 2 GPs...add them up to get the answer as B)
cheers!!