Quantitative Aptitude Ques 1317
Question: The value of (?) in expression $ {7^{8.9}}+{{(343)}^{1.7}}\times {{(49)}^{4.8}}={7^{?}} $ is
Options:
A) 13.4
B) 12.8
C) 11.4
D) 9.6
E) None of these
Show Answer
Answer:
Correct Answer: A
Solution:
- $ {7^{?}}={7^{8.9}}\div {{(343)}^{1.7}}\times {{(49)}^{4.8}} $
$ \Rightarrow $ $ {7^{?}}=\frac{{7^{8.9}}\times {{(7^{2})}^{4.8}}}{{{(7^{3})}^{1.7}}} $
$ \Rightarrow $ $ {7^{?}}=\frac{{7^{8.9,+9.6}}}{{7^{5.1}}} $
$ \Rightarrow $ $ {7^{?}}=\frac{{7^{18.5}}}{{7^{5.1}}} $
$ \Rightarrow $ $ {7^{?}}={7^{18.5-5.1}}={7^{13.4}} $
$ \Rightarrow $ $ ?=13.4 $
BETA
