Aptitude Discussion

Q. |
A boat goes 30 km. upstream and 44 km. downstream in 10 hours. In 13 hours, it can go 40 km upstream and 55 km down-stream. The speed of the boat in still water is: |

✖ A. |
3 km/hr |

✖ B. |
4 km/hr |

✔ C. |
8 km/hr |

✖ D. |
6 km/hr |

**Solution:**

Option(**C**) is correct

If $B$ = speed of boat in still water

$R$ = speed of stream

Then as per the question:

\(\dfrac{30}{(B-R)}+\dfrac{44}{(B-R)}=10\)---------(i)

\(\dfrac{40}{(B-R)}+\dfrac{55}{(B-R)}=13\)---------(ii)

On solving both the equations we get: $B$ = **8 km/hr**

**Nitu**

*()
*

Sorry its downstream

There is an error in answer It should be B+R while taking upstream.