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$32 \times 38 = 30 \times 40 + 2 \times 8$

$34 \times 36 = 30 \times 40 + 4 \times 6$

$56 \times 54 = 50 \times 60 + 6 \times 4$

$73 \times77 = 70 \times80 + 3 \times 7$


And so on?

Verify and generalise if possible.