48÷1/6 can be turned into 48/1÷1/6
Now, when you divide fraction you have to change it to multiplication and then turn 1/6 over. So, now its 48/1× 6/1.
48×6=288. So, the denominator now is 288 and the denominator is 1 since 1×1=1.
Finally you get your answer which is 288/1 which is also 288.