How many planks each of which is `2m` long, `2. 5 cm ` broad and `4cm ` thick can be cut-off from a wooden block `6m ` long, `15 cm` broad and `40 cm` thick?

Explanation

To solve the problem of how many planks can be cut from a wooden block, we need to follow these steps:

### Step 1: Convert all measurements to the same unit
We have the dimensions of the wooden block in meters and centimeters. To simplify calculations, we will convert everything to centimeters.

- Length of the wooden block:
\[
6 \text{ m} = 6 \times 100 = 600 \text{ cm}
...