Question

(0)
A motor boat whose speed is 15 km/h in still water goes 30
km downstream and comes back in four and a half hours.
The speed of the stream is :
(b) 6km/h
(d) 5 km/h
(a) 46 km/h 9700
(c) 7km/h

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Answer 1

Answer:

Since the speed cannot be negative thus, x=5.

Step-by-step explanation:

It is given that speed of motor boat in still water is 15 km/hr and total distance travelled is 30 km.

Let the speed of the stream be x km/hr then the speed upstream is (15−x) km/hr and speed downstream is (15+x) km/hr.

It is also given that total time taken is 4 hours 30 minutes, therefore,

Time taken to row down the stream is-30/15+x and Time taken to row up the stream is -30/15-x

FURTHER CALCULATION IS IN THE ABOVE 2 PHOTOS