Question

Для ремонта железной ветки на участке длиной 240 метров использовали рельсы длиной 9 метров и 12 метров.Девятиметровых рельсов уложили 20 штук.Сколько уложили девятиметровых рельсов?

Answer 1

1) 9 * 20 = 180 (м) - уложили девятиметровых рельсов
2) 240 - 180 = 60 (м) - уложили двенадцатиметровых рельсов
3) 60 : 12 = 5 (р.) - двенадцатиметровых 
Ответ: 5 рельсов.

Answer 2

Calculating the Number of 9-Meter Rails Used

To calculate the number of 9-meter rails used for the repair of the 240-meter track, we can use the information provided.

Length of the track: 240 meters Length of the 9-meter rails: 9 meters Number of 9-meter rails used: 20

To find the total length of the 9-meter rails used, we can multiply the length of each rail by the number of rails: Total length of 9-meter rails = Length of each rail * Number of rails

Total length of 9-meter rails = 9 meters * 20 rails Total length of 9-meter rails = 180 meters

So, 180 meters of 9-meter rails were used for the repair of the 240-meter track.

Conclusion

Therefore, the number of 9-meter rails used for the repair of the 240-meter track is 20.