1. **State the problem:** We are given two equations based on the cost of apples and berries:
- Cost of 3 apples and 1 berry is 22
- Cost of 4 apples and 3 berries is 41
We need to find the cost of 7 apples.
2. **Define variables:** Let $a$ be the cost of one apple and $b$ be the cost of one berry.
3. **Write the system of equations:**
$$3a + b = 22$$
$$4a + 3b = 41$$
4. **Solve the system:**
Multiply the first equation by 3 to align the $b$ terms:
$$3(3a + b) = 3 \times 22$$
$$9a + 3b = 66$$
5. **Subtract the second equation from this new equation:**
$$\cancel{9a} + 3b - (\cancel{4a} + 3b) = 66 - 41$$
$$5a = 25$$
6. **Solve for $a$:**
$$a = \frac{25}{5} = 5$$
7. **Find the cost of 7 apples:**
$$7a = 7 \times 5 = 35$$
**Final answer:** The cost of 7 apples is $35$.
Cost Apples Ec698A
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