Answer: 8 hours
Step-by-step explanation: You would first multiply 2 hours by 4 mph, and get 8 miles. You would then subtract 8 miles from 26 miles, and have 18 miles left. You would now divide 18 miles by 3, as he is now traveling 3 miles per hour and needs to travel 18 miles. You would get 6 hours. You would now add 6 hours by the 2 hours initially traveled at 4 mph, and get 8 hours.
Let A and B be the two complementary angles.
A = smaller angle = 2x
B = larger angle = 13x
x = some unknown number
Note how the ratio A:B turns into 2x:13x which simplifies to 2:13
A+B = 90 ... because the angles are complementary
2x+13x = 90 ... substitution
15x = 90
x = 90/15
x = 6
A = 2*x = 2*6 = 12 degrees
B = 13*x = 13*6 = 78 degrees
The two angles are 12 degrees and 78 degrees.
Check:
A/B = 12/78 = (2*6)/(13*6) = 2/13, so A:B = 2:13
A+B = 12+78 = 90
