Solving Equations 3

$7 (X!) = 840$

$(X!) = 120$

Clearly, X comes out to be 5.

Similarly, $5 (Y!) = 24 \times 5$

And, $(Y!) = 24$

$Y = 4$

$4 (Z!) = 576 \times 5$

$(Z!) = 144 \times 5$

$(Z!) = 2 \times 3 \times 4 \times 5 \times 6$

$Z = 6$

So, Finally, $X \times Y \times Z = 4 \times 5 \times 6 \times =120$