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If a person walks at 14 km/hr instead of 10 km/hr, he would have walked 20 km more. The actual distance travelled by him is:
Answer & Solution
Answer: Option
A
Solution:
$$\eqalign{
& {\text{Let}}\,{\text{the}}\,{\text{actual}}\,{\text{distance}}\,{\text{travelled}}\,{\text{be}}\,x\,km \cr
& {\text{Then}},\,\frac{x}{{10}} = \frac{{x + 20}}{{14}} \cr
& \Rightarrow 14x = 10x + 200 \cr
& \Rightarrow 4x = 200 \cr
& \Rightarrow x = 50\,km \cr} $$