The probability that a leap year selected randomly will have 53 Sundays is 2/7. This is because a leap year has 366 days or 52 weeks and 2 odd days, which can be any of the following pairs: {Sunday, Monday}, {Monday, Tuesday}, {Tuesday, Wednesday}, {Wednesday, Thursday}, {Thursday, Friday}, {Friday, Saturday}, {Saturday, Sunday}. Out of these 7 possibilities, only 2 have a Sunday, so the probability of 53 Sundays is 2/7.