In a code language, 972 means 'steel is strong', 298 means 'iron is strong' and 387 means 'iron and steel'. Find the code for 'and'.

Let's decode the statements by comparing them:
1. "972" $\to$ 'steel is strong'
2. "298" $\to$ 'iron is strong'
3. "387" $\to$ 'iron and steel'

* Comparing statements (1) and (2): The common words are 'is' and 'strong', and the common digits are '9' and '2'.
* Comparing statements (1) and (3): The common word is 'steel', and the common digit is '7'. So, 'steel' = 7.
* Comparing statements (2) and (3): The common word is 'iron', and the common digit is '8'. So, 'iron' = 8.

In statement (3), "387" represents 'iron and steel'.
Since 'iron' is $8$ and 'steel' is $7$, the remaining digit '3' must represent 'and'.