Question

Подводная лодка идя со скоростью 15, 6 км/ч пришла к месту назначения за 2 час 15 мин. С какой скоростью она должна была бы идти, чтобы пройти весь путь на 45 мин скорее? Помогите плиз:)

Answer 1

3 ч 45 мин = 3,75 ч

30 мин = 0,5 ч

15,6 * 3,75 = 58,5 км прошла лодка

3,75 - 0,5 = 3,25 ч время которое должна затратить

58,5 : 3,25 = 18 км/ч скорость с которой лодка должна идти.

Answer 2

Problem Analysis

We are given that a submarine traveled a certain distance at a speed of 15.6 km/h and arrived at its destination in 2 hours and 15 minutes. We need to find the speed at which the submarine should have traveled in order to cover the entire distance 45 minutes faster.

Solution

To find the speed at which the submarine should have traveled, we can use the formula:

Speed = Distance / Time

Let's calculate the distance traveled by the submarine using the given information.

The time taken by the submarine to reach its destination is 2 hours and 15 minutes, which can be converted to hours by dividing by 60:

2 hours + 15 minutes = 2 + 15/60 = 2.25 hours

Now, we can calculate the distance using the formula:

Distance = Speed * Time

Substituting the given values:

Distance = 15.6 km/h * 2.25 hours

Let's calculate the distance:

Distance = 15.6 km/h * 2.25 hours = 35.1 km

Now, we need to find the speed at which the submarine should have traveled to cover the entire distance 45 minutes faster. We can calculate the new time taken using the formula:

Time = Distance / Speed

Substituting the given values:

Time = 35.1 km / (2 hours + 15 minutes - 45 minutes)

Let's calculate the new time:

Time = 35.1 km / (2.25 hours - 0.75 hours) = 35.1 km / 1.5 hours = 23.4 km/h

Therefore, the submarine should have traveled at a speed of 23.4 km/h in order to cover the entire distance 45 minutes faster.

Answer

The submarine should have traveled at a speed of 23.4 km/h in order to cover the entire distance 45 minutes faster.