I drove to the beach at a rate of $40$ miles per hour. If I had driven at a rate of $55$ miles per hour instead, then I would have arrived $25$ minutes earlier. How many miles did I drive?
distance / rate = time
d/40 = d/55 + 25/60 <===== Given ... solve for 'd'
3/440 d = 25/60
d = 61 1/9 miles