Question

Аня,Таня и Ваня собирали марки о космосе. У Ани и Тани вместе 40 марок, у Тани и Вани 50 марок, а у Ани и Вани 70 марок о космосе. Сколько марок о космосе у Ани?

Answer 1

 У Ани -30 марок

У Тани -10 марок

 У вани -40 марок

 

 

 

 

Answer 2

Аня, таня и Ваня собирали марки о космосе. У Ани и Тани вместе 40 марок, у Тани и Вани 50 марок, а у Ани и Вани 70 марок о космосе. Сколько марок о космосе у Ани?

40+50=90

90-70=20

20\2=10  м у Тани

40-10=30 м у Ани

70-30=40 у Вани

Answer 3

Solving the Problem

To solve this problem, we can use a system of equations to find the number of space stamps each person has. Let's denote the number of space stamps Anna has as A, the number of space stamps Tanya has as T, and the number of space stamps Vanya has as V.

We are given the following information: 1. A + T = 40 2. T + V = 50 3. A + V = 70

We can solve these equations to find the value of A.

Calculating the Number of Stamps

First, we can add equations 1 and 2 to eliminate T: A + T + T + V = 40 + 50 This simplifies to: A + 2T + V = 90 (Equation 4)

Next, we can add equations 2 and 3 to eliminate V: T + V + A + V = 50 + 70 This simplifies to: A + T + 2V = 120 (Equation 5)

Now, we can subtract equation 4 from equation 5 to eliminate T and V: (A + T + 2V) - (A + 2T + V) = 120 - 90 This simplifies to: T - V = 30 (Equation 6)

We can use equation 1 to express T in terms of A: T = 40 - A (Equation 7)

Substitute equation 7 into equation 6: 40 - A - V = 30 This simplifies to: V = 10 + A (Equation 8)

Now, we can substitute equation 7 and equation 8 into equation 3: A + (10 + A) = 70 This simplifies to: 2A + 10 = 70 Solving for A: 2A = 60 A = 30

Conclusion

Therefore, Anna has 30 space stamps.

This calculation is based on the given information and the solution is derived using a system of equations.