Ritu can row downstream 20km in 2 hrs and upstream 4km in 2 hrs. find the speed of rowing in still water and the speed of the current

Speed of boat in still water is 6km/h

Speed of current is 4km/h

Step-by-step explanation:

We know speed = distance / time

Let the speed of boat in still water be x

Let the speed of current be y

Hence the speed of boat, down stream =

Distance downstream = 20km

Time taken = 2 hours

We have

      ......(1)

Speed of boat upstream =

Distance upstream = 4

Time taken = 2

We have

   ...(2)

Adding (1) & (2)

Substituting in (1) we get

step-by-step explanation:

c.

step-by-step explanation:

because first you have to add the 4x, 9x, and the 7x together and you get 20x and then you add the last numbers up and you get 5and then you put the subtraction sign in there and that's how you get the answer.