1. **State the problem:** We need to find the weight of each red block and each green block given two conditions:
- 3 red blocks and 4 green blocks weigh 20 lbs.
- 2 red blocks and 6 green blocks weigh 25 lbs.
2. **Set variables:** Let $r$ be the weight of one red block and $g$ be the weight of one green block.
3. **Write the system of equations:**
$$3r + 4g = 20$$
$$2r + 6g = 25$$
4. **Solve the system:**
Multiply the first equation by 2 and the second by 3 to align coefficients of $r$:
$$2(3r + 4g) = 2(20) \Rightarrow 6r + 8g = 40$$
$$3(2r + 6g) = 3(25) \Rightarrow 6r + 18g = 75$$
5. **Subtract the first new equation from the second:**
$$\cancel{6r} + 18g - (\cancel{6r} + 8g) = 75 - 40$$
$$18g - 8g = 35$$
$$10g = 35$$
6. **Solve for $g$:**
$$g = \frac{35}{10} = 3.5$$
7. **Substitute $g=3.5$ into the first original equation:**
$$3r + 4(3.5) = 20$$
$$3r + 14 = 20$$
8. **Solve for $r$:**
$$3r = 20 - 14 = 6$$
$$r = \frac{6}{3} = 2$$
**Final answer:**
- Each red block weighs $2$ lbs.
- Each green block weighs $3.5$ lbs.
Block Weights 964433
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