Question

Из пункта А отправился автомобиль "москвич" со скоростью 70 км/ч. спустя 45 мин. из пункта В, удаленного от А на 17,5 км, вслед за ним выехали "жигули" со скоростью на 20% большей. сколько времени потребуется "жигулям", чтобы догнать "москвич"

Answer 1

Vмоскв.-70км/ч: Vжигул.=1.2Vмоскв.=1.2*70=84км/чЗа 45мин.(3/4часа) москвич проедет:S=Vм*t=70*3/4=52.5кмУдаленность от пункта В (начало движения жигулей) до москвича составит:S=52.5+17,5=70кмСоставляем уравнение;Vжиг*t-S=Vмоск*t84t-70=70t14t=70t=5часовОтвет;жигулям потребуется 5 часов чтоб догнать москвич. 

Answer 2

Calculation of Time Required for the "Zhiguli" to Catch up to the "Moskvich"

To calculate the time required for the "Zhiguli" to catch up to the "Moskvich," we need to consider the speeds and distances involved.

Given information: - The "Moskvich" car travels at a speed of 70 km/h. - The "Zhiguli" car travels at a speed that is 20% higher than the "Moskvich."

Let's break down the problem step by step:

1. Calculate the speed of the "Zhiguli" car: - The "Zhiguli" car travels at a speed that is 20% higher than the "Moskvich." - 20% of 70 km/h is 14 km/h. - Therefore, the speed of the "Zhiguli" car is 70 km/h + 14 km/h = 84 km/h.

2. Calculate the time it takes for the "Moskvich" car to travel from point A to point B: - The distance between point A and point B is given as 17.5 km. - The "Moskvich" car travels at a speed of 70 km/h. - Using the formula: time = distance / speed, we can calculate the time it takes for the "Moskvich" car to travel from point A to point B. - time = 17.5 km / 70 km/h = 0.25 hours = 15 minutes.

3. Calculate the time it takes for the "Zhiguli" car to catch up to the "Moskvich": - The "Zhiguli" car starts its journey 45 minutes after the "Moskvich" car. - Convert 45 minutes to hours: 45 minutes / 60 minutes = 0.75 hours. - The "Zhiguli" car travels at a speed of 84 km/h. - The "Moskvich" car has a head start of 17.5 km. - The relative speed between the two cars is 84 km/h - 70 km/h = 14 km/h. - Using the formula: time = distance / relative speed, we can calculate the time it takes for the "Zhiguli" car to catch up to the "Moskvich." - time = 17.5 km / 14 km/h = 1.25 hours = 1 hour and 15 minutes.

Therefore, it will take the "Zhiguli" car 1 hour and 15 minutes to catch up to the "Moskvich" car.

Note: The calculations provided above are based on the given information and assumptions made.