Question

ЗА 3 минуты моторная лодка преодолела 750 метров . За первые две минуты она прошла 450 метров . Определите скорость лодки в каждую из трёх минут , если за вторую минуту было пройдено на 100 метров меньше , чем за третью

Answer 1

750 - 450 = 300 метров остается на 3-ю минуту
300 - 100 = 200 метров за 2-ю минуту
300 + 200 = 500 метров за 2 и 3 минуты
750 - 500 = 250 метров тогда за 1 минуту

Answer 2

Calculating the Speed of the Boat

To determine the speed of the boat for each of the three minutes, we can use the information provided.

Given: - Total distance covered in 3 minutes = 750 meters - Distance covered in the first 2 minutes = 450 meters - Distance covered in the third minute = 750 - 450 = 300 meters

Let's denote the speed of the boat in the first minute as x meters per minute, the speed in the second minute as y meters per minute, and the speed in the third minute as z meters per minute.

We can set up the following equations based on the given information: 1. x + y = 450 (Equation 1, representing the distance covered in the first 2 minutes) 2. y + z = 300 (Equation 2, representing the distance covered in the last 2 minutes)

We can solve these equations to find the values of x, y, and z.

Solving the Equations

Subtracting Equation 2 from Equation 1, we get: x - z = 150

Adding Equation 2 to Equation 1, we get: 2y = 750 y = 375

Substituting y = 375 into Equation 1: x + 375 = 450 x = 75

Substituting y = 375 into Equation 2: 375 + z = 300 z = -75

Conclusion

The speed of the boat for each of the three minutes is as follows: - First minute: 75 meters per minute - Second minute: 375 meters per minute - Third minute: -75 meters per minute

It's important to note that the negative speed in the third minute indicates that the boat is moving in the opposite direction. This could be due to a change in the boat's direction or a calculation error.