(12 2/3)*(3 1/4) = 41 1/6 . . . . . according to my calculator
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You are usually taught to multiply the improper fractions and simplify the result.
.. (38/3)*(13/4) = (38/4)*(13/3)
.. = (19/2)*(13/3)
.. = (19*13)/6
.. = 247/6
.. = 41 1/6
You can also multiply the parts.
.. (12 2/3)*(3 1/4) = 12*3 + 12*(1/4) +(2/3)*3 +(2/3)*(1/4)
.. = 36 +3 +2 +1/6
.. = 41 1/6