A man is crossing a river of width 100 m on a motorboat. The velocity of the motor boat is 4 m/s eastward and the velocity of the water current is 3 m/s northward. What is the resultant velocity of the boat and how much time will it take for the man to reach the other shore of the river?

The resultant velocity of the boat = 5 m/s

The time it will take for the man to reach the other shore of the river =  25 s

Explanation:

width of river = 100 m

The velocity of the motorboat = 4 m/s eastward

The velocity of the water current = 3 m/s northward

The resultant velocity of the boat is:

R^2 = 4^2 + 3^2

= √ (4^2) + (3^2)

= √16 + 9

=√25

= 5 m/s

The time it will take for the man to reach the other shore of the river is:

d = 100 m

v = 4 m/s

t = d / v

t = 100 / 4

t =  25 s

correct it is c.) b b

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form