CBSE Class 12-science Answered

 a leap year has 366 days. i.e. it has 52 weeks and 2 days extra.These 2 days can be any one of the following 7 combinations.

Mon-Tue, Tue-Wed, Wed-Thu, Thu-Fri, Fri-Sat,Sat-Sun,Sun-Mon

If we want to have only 52 tuesdays, then one of  the 2 extra days can't  be a tuesday.So it can be anyone of the combinationsas given below.

Sun-Mon,Wed-Thu,Thu-Fri,Fri-Sat,Sat-Sun.

The total pairs are 7 , out of which the event is favourable to only 5 cases.

So the required prob is 5/7.