Perform the indicated operation 5/4 + 7/9

In order to add fractions you must have common denominators so you need to multiply 5/4 by 9 and 7/9 by 4
the new fractions will be 45/36 + 28/36
now you add the numerators but do not add the denominator
the answer should be 73/36

I’m not absolutely sure but i think it’s 7x6x5x4x3x2=5040 because as the first character you can take any of the 7 given then you are left with 5 then 6 then 4 etc.