How do you multiply two numbers just below 100, e.g. 97 × 94 (the Nikhilam method)?

Take each number's shortfall from 100; the left part is one number minus the other's shortfall, the right part is the product of the shortfalls (two digits).

97 × 94 → shortfalls −3 and −6:

• Left: 97 − 6 = 91 (equivalently 94 − 3 = 91).
• Right: 3 × 6 = 18 (fills the two-digit slot).
• Answer: 91 | 18 = 9118.

Check: 97 × 94 = 9118. ✓ "All from 9 and the last from 10" gives the shortfalls; cross-subtract for the left, multiply shortfalls for the right.