Question

Петр шел из села к озеру 0,7 ч по одной дороге, а возратился по другой дороге за 0,8 ч, пройдя всего 6,44 км. С какой скоростью шел Петр к озеру, если возращался он со скоростью 3,5 км/ч? ПО ДЕЙСТВИЯМ, ЗАРАНЕЕ СПАСИБО)))

Answer 1

3,5*0,8=2,8(км)-обратно
6,44-2,8=3,64(км)-туда
3,64/0,7=5,2(км/ч)-V туда

Answer 2

#### Problem Analysis We are given that Peter walked from a village to a lake in 0.7 hours using one road, and returned using a different road in 0.8 hours. The total distance covered was 6.44 km. We also know that Peter returned at a speed of 3.5 km/h. We need to find out at what speed Peter walked to the lake. #### Solution Let's assume that Peter walked to the lake at a speed of **x km/h**. We can use the formula **speed = distance / time** to calculate the distance Peter walked to the lake. The distance Peter walked to the lake can be calculated using the formula **distance = speed * time**. From the given information, we have: - Time taken to walk to the lake = 0.7 hours - Distance covered while returning = 6.44 km - Time taken to return = 0.8 hours - Speed while returning = 3.5 km/h Using the formula **distance = speed * time**, we can calculate the distance Peter covered while returning: **distance = 3.5 km/h * 0.8 hours = 2.8 km**. Since the total distance covered is 6.44 km, we can subtract the distance covered while returning from the total distance to find the distance Peter walked to the lake: **distance to the lake = total distance - distance covered while returning = 6.44 km - 2.8 km = 3.64 km**. Now, we can use the formula **speed = distance / time** to find the speed at which Peter walked to the lake: **x km/h = 3.64 km / 0.7 hours**. Let's calculate the speed: ```python distance_to_lake = 3.64 # km time_to_lake = 0.7 # hours speed_to_lake = distance_to_lake / time_to_lake speed_to_lake ``` The speed at which Peter walked to the lake is approximately **5.2 km/h**. #### Answer Peter walked to the lake at a speed of approximately **5.2 km/h**. #### Verification To verify the answer, we can calculate the time taken to walk to the lake using the formula **time = distance / speed**: ```python distance_to_lake = 3.64 # km speed_to_lake = 5.2 # km/h time_to_lake = distance_to_lake / speed_to_lake time_to_lake ``` The time taken to walk to the lake is approximately **0.7 hours**, which matches the given information. Therefore, the answer is verified.