Question

рАССТОЯНИЕ МЕЖДУ ДВУМЯ ПУНКТАМИ ПОЕЗД ПРОХОДИТ ПО РАССПИСАНИЮ ЗА 7 ЧАСОВ. Через 6 ч после отправления он снизил скорость на 10 км/ч., поэтому в конечнвй пункт проишел с опозданием на 10 мин. Найдите первоначальную скорость поезда.

Answer 1

пусть х км/ч первонач. скорость,(х-10) уменьшенная скорость

7х=6х+1 1/6(х-10)

х- 7/6  х=-70/6

-1/6 х=-70/6

х=70 км/ч нач. скорость

х-10=60 км/ч уменьшинная скорость 

Answer 2

Calculating the Initial Speed of the Train

To calculate the initial speed of the train, we can use the information provided about the distance, time, and the change in speed.

Given: - The train travels a certain distance in 7 hours according to the schedule. - After 6 hours, the train reduces its speed by 10 km/h and arrives at the final destination 10 minutes late.

Let's denote: - Initial speed of the train as v (in km/h). - Distance between the two points as d (in km).

The total time taken by the train at the reduced speed is 7 hours and 10 minutes, which is 7.167 hours.

Using the formula: \[ \text{time} = \frac{\text{distance}}{\text{speed}} \]

We can set up the following equations:

1. For the initial speed: \[ \frac{d}{v} + \frac{d}{v-10} = 7.167 \]

2. For the delay: \[ \frac{d}{v} - \frac{d}{v-10} = \frac{1}{6} \]

Let's solve these equations to find the initial speed of the train.

Solving the Equations

The solution to the equations will provide us with the initial speed of the train.

\[ \frac{d}{v} + \frac{d}{v-10} = 7.167 \] \[ \frac{d}{v} - \frac{d}{v-10} = \frac{1}{6} \]

Solving these equations will give us the initial speed of the train.