Question

Расстояние 287 км электропоезд прошел за 4 часа.За первый час поезд прошел 71 целая 5/8 км,за второй 69 целых 4/15 км, за третий 75 целых 3/8 км.Сколько километров поезд прошел за четвертый час

Answer 1

$1)71\tt\displaystyle\frac{5}{8}+69\frac{4}{15}=71\frac{75}{120}+69\frac{32}{120}=140\frac{107}{120}$ - км прошёл поезд за 1й и 2й час

$2)140\tt\displaystyle\frac{107}{120}+75\frac{3}{8}=140\frac{107}{120}+75\frac{45}{120}=215\frac{152}{120}=216\frac{32}{120}=216\frac{4}{15}$ км - прошёл поезда за 3 часа

$3)287-216\tt\displaystyle\frac{4}{15}=286\frac{15}{15}-216\frac{4}{15}=70\frac{11}{15}$ км - прошёл поезд за 4й час

Ответ: за четвёртый час поезд прошёл 70  11/15 км.

Answer 2

Calculation of Distance Traveled by the Train

To calculate the distance traveled by the train in the fourth hour, we need to subtract the distances traveled in the first three hours from the total distance of 287 km.

Let's calculate the distances traveled in the first three hours:

- In the first hour, the train traveled 71 5/8 km. - In the second hour, the train traveled 69 4/15 km. - In the third hour, the train traveled 75 3/8 km.

Now, let's calculate the total distance traveled in the first three hours:

71 5/8 km + 69 4/15 km + 75 3/8 km = 216 13/120 km

To find the distance traveled in the fourth hour, we subtract this total distance from the total distance of 287 km:

287 km - 216 13/120 km = 70 107/120 km

Therefore, the train traveled 70 107/120 km in the fourth hour.

Please note that the fractions have been simplified for clarity.

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