A) 32
B) 50
C) 40
D) 36
Correct Answer: B
Solution :
Let the total distance = y Speed of A = 4x and speed of \[B=5x\] Time taken by B = 40 minutes \[\frac{y}{5x}=40\,\,\,\Rightarrow \,\,\,\frac{y}{x}=200\] ?..(i) Time taken by A to cover same distance \[=\frac{y}{4x}=\frac{200}{4}=\,\underline{\mathbf{50}\,\mathbf{minutes}}\] Shortcut: The speed in the ratio of\[4:5\]. So, the time taken will be in the ratio of\[5:4\]. Then, Time taken by \[A=\frac{5}{4}\times 40=\underline{\mathbf{50}\,\mathbf{minutes}}\]You need to login to perform this action.
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