Question

Велосипедист сначала ехал со скоростью 12км/ч, затем 15км/ч. Весь путь 96 км. Сколько времени двигался велосипедист со скоростью 12 км/ч

Answer 1

12x+15y=96.Допустим что x =3.тогда 96-36=60.y=60:15=4.

Ответ:3 со скоростью 12 и 4 со скоростью 15.

Answer 2

решение: 96/12=8часов

Answer 3

Calculation of Time at 12 km/h and 15 km/h

To calculate the time the cyclist spent traveling at a speed of 12 km/h, we need to determine the distance covered at that speed. We know that the total distance traveled is 96 km, and the cyclist initially traveled at a speed of 12 km/h before increasing to 15 km/h.

Let's denote the time spent at 12 km/h as t1 and the time spent at 15 km/h as t2.

To find t1, we can use the formula: distance = speed × time.

At a speed of 12 km/h, the distance covered is 12t1.

To find t2, we can use the same formula: distance = speed × time.

At a speed of 15 km/h, the distance covered is 15t2.

Since the total distance covered is 96 km, we can write the equation: 12t1 + 15t2 = 96.

We need to solve this equation to find the values of t1 and t2.

Let's solve the equation:

12t1 + 15t2 = 96

We can divide the equation by 3 to simplify it:

4t1 + 5t2 = 32

Now we have a system of equations:

4t1 + 5t2 = 32 (Equation 1) t1 + t2 = 8 (Equation 2)

We can solve this system of equations using substitution or elimination.

Let's solve it using elimination:

Multiply Equation 2 by 4:

4t1 + 4t2 = 32 (Equation 3)

Subtract Equation 3 from Equation 1:

4t1 + 5t2 - (4t1 + 4t2) = 32 - 32

t2 = 0

Substitute t2 = 0 into Equation 2:

t1 + 0 = 8

t1 = 8

Therefore, the cyclist spent 8 hours traveling at a speed of 12 km/h.

Answer:

The cyclist traveled at a speed of 12 km/h for 8 hours.