This appears to be a type of pattern or rule-based question rather than a straightforward arithmetic one. Let's analyze the given pattern:

1. $54 = 36$
2. $63 = 30$

Looking at the first pair:

For $54 = 36$:

• If we subtract the digits of 54, we get $5 - 4 = 1$.
• Then, $54 - 18 \times 1 = 36$, where 18 is some adjustment.

For $63 = 30$:

• Subtracting the digits of 63 gives $6 - 3 = 3$.
• Then, $63 - 11 \times 3 = 30$, where 11 is the new factor.

However, this is speculative, and a definite answer to $7 \times 5$ using a similar subtraction-based rule would result in analyzing those terms similarly.

Would you like further analysis of this logic?