7.42 as a fraction is 7420/1000. Now you need to simplify it. The easiest way to do this is to continuously divide the top and bottom by 2 as long as it is even. At this point it should be small enough to figure out the other factors, and finish simplifying it. This only simplifies to 371/50. While 371 is divisible by 7 and 53, 50 is not divisible by either of them, so the final solution is 371/30