The answer is no because it fails the vertical line test
3x/8 divided by 7y/4
you can not divide fractions, so you must multiply by the reciprocal.
3x/8 x 4/7y now you can simplify the 4 and 8
3x/2 x 1/7y now multiply across
3x/2(7y)
3x/14y should be your answer