June 25, 1982, fell on a Friday. On which day of the week did June 25, 1987, fall? (Note: 1984 was a leap year.)

[Gmat_mission]

June 25, 1982, fell on a Friday. On which day of the week did June 25, 1987, fall? (Note: 1984 was a leap year.)

A. Sunday
B. Monday
C. Tuesday
D. Wednesday
E. Thursday

Answer: E

Source: GMAT Prep

[psarma]

June 25, 1982 was a friday
365 days in a regular year, which is 7X52 + 1, so if a given day is friday, then that day + 365 days is the next calendar day
June 25, 1983 was thus a Saturday
1984 was a leap year, so one extra day in Feb, making June 25, 1984 a Monday (instead of Sunday)
No more leap years until 1987
So june 25, 1985 was Tuesday,
So june 25, 1986 was Wednesday
and june 25, 1987 was Thursday

[Scott@TargetTestPrep]

June 25, 1982, fell on a Friday. On which day of the week did June 25, 1987, fall? (Note: 1984 was a leap year.)

A. Sunday
B. Monday
C. Tuesday
D. Wednesday
E. Thursday

Answer: E

Source: GMAT Prep

Solution:

Since June 25, 1987 is exactly 5 years after June 25, 1982. Including the 1 extra leap day in 1984, 5 x 365 + 1 = 1826 days have elapsed between the two dates. Since 1826/7 = 260 R 6, we see that 260 weeks and 6 days have elapsed between the two dates. Since June 25, 1982 fell on a Friday and June 25, 1987 would be 6 days after Friday, June 25, 1987 fell on a Thursday.

Answer: E