Principle: Pythagorean theorem
Given:
Let a = boat velocity = 25 miles per hour
b = river velocity = 10 miles per hour
Required: c = actual velocity
Solution:
c^2 = a^2 + b^2
c^2 = (25)^2 + (10)^2
c^2 = 725
(c^2)^0.5 = (725)^0.5
c = 26.93 miles per hour
ANSWER: Actual boat velocity is 26.93 miles per hour