Question

На изготовление первой детали токарь затратил 8/15 часа,на изготовление второй в 4 раза меньше,чем первой ,а на изготовление третьей на 1 целую 3/5 часа больше,чем на изготовление первой.Сколько времени заняло у токаря изготовление трёх деталей?

Answer 1

1) 60:15*8=32 мин -на первую дет
2)32:4=8 мин -на изгот 2 дет
1и 3/5 часа =96мин  
3)32+96=128 мин на третью
4)32+8+128=168 мин=2 часа48 мин - на все детали

Answer 2

Calculating Time Taken to Make Three Parts

To calculate the total time taken by the lathe operator to make three parts, we can use the given information about the time taken to make each part.

1. Time Taken for First Part: - The lathe operator spent 8/15 hours to make the first part.

2. Time Taken for Second Part: - The time taken to make the second part is 4 times less than the time taken for the first part.

3. Time Taken for Third Part: - The time taken to make the third part is 1 hour and 3/5 hours more than the time taken for the first part.

Calculations

Let's calculate the time taken for each part and then find the total time taken for all three parts.

1. Time Taken for First Part: - Given: 8/15 hours

2. Time Taken for Second Part: - 4 times less than the time taken for the first part: - 8/15 * 4 = 32/15 hours

3. Time Taken for Third Part: - 1 hour and 3/5 hours more than the time taken for the first part: - 8/15 + 1 + 3/5 = 8/15 + 1 + 3/5 = 8/15 + 1 + 9/15 = 1 + 17/15 = 2 + 2/15 hours

Total Time Taken

To find the total time taken for all three parts, we add the time taken for each part.

Total time taken = Time for first part + Time for second part + Time for third part Total time taken = 8/15 + 32/15 + 2 + 2/15 Total time taken = 42/15 + 2 + 2/15 Total time taken = 14/5 + 2 + 2/15 Total time taken = 2 + 4/5 + 2/15 Total time taken = 2 + 12/15 + 2/15 Total time taken = 2 + 14/15 Total time taken = 2 + 14/15 Total time taken = 2 + 14/15 Total time taken = 2 14/15 hours

So, the lathe operator took 2 hours and 14 minutes to make three parts.