Answer:

Step-by-step explanation:
The systems of equations are
Let us assume the rate of the current be c
Now actual speed against the current is (15 - c)
And, the actual speed with the current is (15 + c)
Here we applied the time formula i.e. distance by speed
Also the upstream time - downstream time = 4
Now the equations are

Answer:
164$
Step-by-step explanation:
18 percent of 200 is 36.
so subtract the 36 from 200 and get 164
The answer is 2(3x-y)+5(x+2y).