The circumference of the front wheel of a special bike is 0.6 m less than the circumference of the rear wheel.
The circumference of the front wheel of a special bike is 0.6 m less than the circumference of the rear wheel. At a distance of 36 m, the front wheel makes 5 revolutions more than the rear one. Find the circumference of each wheel.
Suppose that the circumference of the rear wheel is x meters, then the circumference of the front wheel is x – 0.6 meters.
At a distance of 36 meters, the rear wheel will make 36 / x revolutions, and the front, respectively, will make 36 / (x – 0.6) revolutions.
According to the condition of the problem, we compose the equation:
36 / (x – 0.6) = 36 / x + 5,
36 / (x – 0.6) = (36 + 5 * x) / x,
36 * x = 36 * x – 21.6 + 5 * x² – 3 * x,
5 * x² – 3 * x – 21.6 = 0.
Let’s find the discriminant of this equation:
D = (-3) ² – 4 * 5 * (-21.6) = 9 + 432 = 441.
Therefore, the equation has the following solutions:
x = (3 – 21) / 10 = – 1.8 and x = (3 + 21) / 10 = 2.4.
Since x can only be a positive number, the circumference of the second wheel is 2.4 meters, and the first, respectively, 2.4 – 0.6 = 1.8 meters.
Answer: 1.8 meters and 2.4 meters.