Question

Помогите решить задачу!!!!!! За 8 одинаковых по цене карандашей Ира заплатила 16р. Какова стоимость 4-х таких карандашей? Реши задачу двумя способами.

Answer 1

Решение 1:
1)16:8=2(руб.)-За 1 карандаш.
2)2×4=8(Руб.)-За 4 карандаша.
Ответ:стоимость 4 карандашей 8 рублей.
Решение 2:
16:8×4=8

Answer 2

Problem Analysis

To solve this problem, we need to find the cost of 4 pencils given that 8 pencils cost 16 rubles. We can solve this problem using two different methods.

Method 1: Proportions

We can set up a proportion to find the cost of 4 pencils. Let's assume the cost of 4 pencils is x rubles. The proportion can be set up as follows:

8 pencils / 16 rubles = 4 pencils / x rubles

To solve for x, we can cross-multiply and solve for x:

8 * x = 16 * 4

Simplifying the equation:

8x = 64

Dividing both sides by 8:

x = 8

Therefore, the cost of 4 pencils is 8 rubles.

Method 2: Division

Another way to solve this problem is by dividing the cost of 8 pencils by the number of pencils to find the cost of 1 pencil, and then multiplying it by 4 to find the cost of 4 pencils.

The cost of 1 pencil is:

16 rubles / 8 pencils = 2 rubles/pencil

To find the cost of 4 pencils, we can multiply the cost of 1 pencil by 4:

2 rubles/pencil * 4 pencils = 8 rubles

Therefore, the cost of 4 pencils is 8 rubles.

Conclusion

Using both methods, we have determined that the cost of 4 pencils is 8 rubles.

I hope this helps! Let me know if you have any further questions.