Question

На столе лежат ручки, карандаши и маркеры всего-45 штук. Ручек на 10 больше, чем маркеров, но на 10 меньше чем карандашей. Сколько ручек, карандашей и маркеров лежит на столе?

Answer 1

Пусть ручек - x
Тогда карандашей х+10, а маркеров x-10
Составим уравнение
х+10+х+х-10=45
3х=45-10+10
3х=45
х=45/3
x=15
15 ручек 5 маркеров и 25 карандашей

Answer 2

Calculating the Number of Pens, Pencils, and Markers

To solve this problem, we can use a system of equations based on the given information. Let's denote the number of pens as P, the number of pencils as C, and the number of markers as M.

We are given the following information: 1. The total number of pens, pencils, and markers is 45: P + C + M = 45. 2. The number of pens is 10 more than the number of markers: P = M + 10. 3. The number of pens is 10 less than the number of pencils: P = C - 10.

Solving the System of Equations

We can use the second and third pieces of information to express the number of markers and pencils in terms of pens: - From the second piece of information: M = P - 10. - From the third piece of information: C = P + 10.

Now, we can substitute these expressions into the first equation to solve for the values of P, C, and M.

Substituting M = P - 10 and C = P + 10 into P + C + M = 45: (P) + (P + 10) + (P - 10) = 45 3P = 45 P = 15

Now that we have the value of P, we can find the values of C and M: - C = P + 10 = 15 + 10 = 25 - M = P - 10 = 15 - 10 = 5

Conclusion

Therefore, there are 15 pens, 25 pencils, and 5 markers on the table.