A leap year contain 366 days
No. Of days 365
A leap year has 53 sundays and the other two days
May be (sat, sun)(sun,mon) (mon,tues) (tues,wed)(wed,thur)(thur,fri)(fri,sat)
Total no. Of all possible outcome is 7
Let e b the getting 53 sun in leap year
No. Of favourable outcome is n(e) is 2
No. Of all possible outcome n(s) is 7
P(e)=n(e)/n(s)= 2/7
the no. of days of a leap year =366 days.
in a leap year there will be 52 weeks
and 2 extra days.
therefore there will be 52 sundays
compulsarily the remaining 2 days can be
mon.  tues.
tues.  wed.
wed.  thurs.
thurs.  fri.
fri.      sat.
sat.  sun.
sun.  mon.
these will be the possibilities .
n(e) = 2 (because in the 7 possibilities 2 contain sundays)
n(s) = 7 (total possibilities.)
P(e) = 2/7

pls. mark as best if it is clear.