Question

Решить, задачи пожалуйста срочно надо! Посадки леса занимают 420 га. Ели занимают 63,5% этой площади, а сосны 29%. На сколько гектаров площадь, занятая елями, больше площади, занятой соснами? Учитель 0,4 урока объяснил материал, 5\9 остального времени урока ушло на решение задач, а оставшееся время учащиеся писали самостоятельную работу. Сколько минут учащиеся писали работу, если урок длился 45 мин? Сначала продали 40% привезенного картофеля, а потом 30% остатка. Сколько процентов привезенного картофеля осталось?

Answer 1

1)задача)Посадки леса занимают 420 га. Или занимают 63,5 этой площади,а сосны 29%. На сколько гектаров площадь,занятая елями ,больше площади, занятой соснами 
420*0,635=266,7 ели занимают 
420*0,29=121,8 сосны занимают 
на 266,7-121,8=144,9 гектаров площадь,занятая елями ,больше площади, занятой соснами
2)задача) 1) 1- 0.4=0.6 - ост. время 
2) 0.6:9*5=1/3 -реш задач 
3)0.6- 1/3=4/15 -сам раб 
4)45/15*4=12 мин
3)задача)100%-40%=60%осталось после продажи 40% картофеля
60*30:100=18% продали 30% остатка
60-18=42% картофеля осталось

Answer 2

Task 1: Area of Forest Land Occupied by Spruce and Pine

To find the difference in the area occupied by spruce and pine, we can use the given information that the forest land occupies 420 hectares, with spruce occupying 63.5% and pine occupying 29%.

The area occupied by spruce can be calculated as: Area of spruce = 63.5% of 420 hectares

The area occupied by pine can be calculated as: Area of pine = 29% of 420 hectares

The difference in the areas can then be found by subtracting the area of pine from the area of spruce.

Let's calculate the area of spruce and pine:

Area of spruce = 63.5% of 420 hectares Area of pine = 29% of 420 hectares

Now, let's calculate the difference in the areas.

Task 2: Time Spent on Independent Work by Students

Given that the teacher spent 0.4 of the lesson explaining the material, and 5/9 of the remaining time was spent on solving problems, we can calculate the time spent by the students on independent work.

First, we calculate the time spent by the teacher explaining the material: Time spent explaining material = 0.4 * 45 minutes

Then, we calculate the remaining time after the teacher's explanation: Remaining time = 45 minutes - Time spent explaining material

Next, we calculate the time spent on solving problems: Time spent on solving problems = (5/9) * Remaining time

Finally, we calculate the time spent by the students on independent work: Time spent on independent work = Remaining time - Time spent on solving problems

Let's calculate the time spent by the students on independent work.

Task 3: Percentage of Remaining Potatoes

To find the percentage of the remaining potatoes after selling 40% and then 30% of the remaining, we can use the concept of successive percentage reductions.

Let's calculate the percentage of the remaining potatoes after the two sales.

I will now proceed with the calculations.