A pet shop has 12 fish tanks for sale. Each fish tank has a volume of $400,000 \text{ cm}^3$. We need to find the combined volume of all the fish tanks in $\text{m}^3$.

1. Problem Description

A pet shop has 12 fish tanks for sale. Each fish tank has a volume of $400,000 \text{ cm}^3$. We need to find the combined volume of all the fish tanks in $\text{m}^3$.

2. Solution Steps

First, we find the total volume of all fish tanks in $\text{cm}^3$ by multiplying the number of fish tanks by the volume of each tank.

Total volume in $\text{cm}^3 = 12 \times 400,000 = 4,800,000 \text{ cm}^3$.

Next, we need to convert the volume from $\text{cm}^3$ to $\text{m}^3$.

We know that $1 \text{ m} = 100 \text{ cm}$, so $1 \text{ m}^3 = (100 \text{ cm})^3 = 100^3 \text{ cm}^3 = 1,000,000 \text{ cm}^3$.

Therefore, to convert from $\text{cm}^3$ to $\text{m}^3$, we divide by $1,000,000$.

Total volume in $\text{m}^3 = \frac{4,800,000}{1,000,000} = 4.8 \text{ m}^3$.

3. Final Answer

$4.8$