Irrational is the wrong word, it was a .3 or .6 repeater or something similar. Same effect: pile in digits so excel would round it off correctly back to the original rate I was quoted.
Assuming your day rate was a multiple of 10, it can only have been a .3 or .6 repeater (or an integer), because dividing a multiple of 5 by 7.5 gives you an integer number of thirds.
