Question

Велосипедист поднялся на холм со скоростью 12 км час , а спустился он с холма тем же путем со скоростью 20 км/ч, потратив на спуск на 1/3 часа меньше, чем на подъём. Чему равна длина дороги, ведущей на холм

Answer 1

х/12-х/20=16/60
2х/60=4/15
х/30=4/15
15х=120 
х=8
Ответ: 8 км x/12-x/20=16/60

Answer 2

Calculation of the Length of the Road Leading to the Hill

To calculate the length of the road leading to the hill, we can use the formula:

Distance = Speed × Time

Let's denote the length of the road as "x" kilometers.

During the ascent, the cyclist traveled at a speed of 12 km/h. The time taken for the ascent can be represented as:

Time for ascent = x / 12 hours

During the descent, the cyclist traveled at a speed of 20 km/h. The time taken for the descent is 1/3 hour less than the time taken for the ascent. Therefore, the time for the descent can be represented as:

Time for descent = (x / 20) - (1/3) hours

Since the cyclist traveled the same distance during the ascent and descent, we can equate the two expressions for time:

x / 12 = (x / 20) - (1/3)

To solve this equation, we can multiply both sides by the least common multiple (LCM) of 12 and 20, which is 60:

60 * (x / 12) = 60 * ((x / 20) - (1/3))

Simplifying the equation:

5x = 3x - 20

2x = 20

x = 10

Therefore, the length of the road leading to the hill is 10 kilometers.