A) \[4.5\]
B) \[4.6\]
C) \[4.7\]
D) \[4.8\]
Correct Answer: B
Solution :
Let the numbers be \[{{x}_{1}},{{x}_{2}},{{x}_{3}},{{x}_{4}},{{x}_{5}}\] and \[{{x}_{6}}\]. Average of six numbers \[=3.95\] \[\Rightarrow \] \[\frac{{{x}_{1}}+{{x}_{2}}+{{x}_{3}}+{{x}_{4}}+{{x}_{5}}+{{x}_{6}}}{6}=3.95\] \[\Rightarrow \] \[{{x}_{1}}+{{x}_{2}}+{{x}_{3}}+{{x}_{4}}+{{x}_{5}}+{{x}_{6}}=23.7\] ?.(i) Average of first two numbers \[=3.4\] \[\Rightarrow \] \[\frac{{{x}_{1}}+{{x}_{2}}}{2}=3.4\,\,\,\Rightarrow \,\,\,{{x}_{1}}+{{x}_{2}}=6.8\] ?.(ii) Average of other two numbers \[=3.85\] \[\Rightarrow \] \[\frac{{{x}_{3}}+{{x}_{4}}}{2}=3.85\,\,\,\,\,\,\Rightarrow \,\,\,{{x}_{3}}+{{x}_{4}}=7.7\] ?.(iii) From (i), (ii) and (iii), we get \[6.8+7.7+{{x}_{5}}+{{x}_{6}}=23.7\] \[\Rightarrow \] \[{{x}_{5}}+{{x}_{6}}=23.7-14.5\,\,\Rightarrow \,\,{{x}_{5}}+{{x}_{6}}=9.2\] \[\Rightarrow \]\[\frac{{{x}_{5}}+{{x}_{6}}}{2}=\frac{9.2}{2}=4.6\] \[\therefore \]Average of remaining two numbers \[=4.6\]
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