If you are told that a randomly selected mystery person was born in the 1990's, what is the probability of guessing his/her exact birth date (including year)?
A) $2.740 \times 10 ^ { - 4 }$
B) $2.738 \times 10 ^ { - 4 }$
C) $2.738 \times 10 ^ { - 3 }$
D) $2.737 \times 10 ^ { - 3 }$

Question

If you are told that a randomly selected mystery person was born in the 1990's, what is the probability of guessing his/her exact birth date (including year)? 
A) $2.740 \times 10 ^ { - 4 }$
B) $2.738 \times 10 ^ { - 4 }$
C) $2.738 \times 10 ^ { - 3 }$
D) $2.737 \times 10 ^ { - 3 }$

Quizplus · Accepted Answer

The 1990s span from January 1, 1990, to December 31, 1999, totaling 10 years. Assuming each year has 365 days (ignoring leap years for simplicity), the total number of days in the 1990s is $10 \times 365 = 3650$ days. The probability of guessing the correct day is $1/3650$, which equals approximately $2.738 \times 10^{-4}$.

If You Are Told That a Randomly Selected Mystery Person 2.740×10−42.740 \times 10 ^ { - 4 }2.740×10−4

If You Are Told That a Randomly Selected Mystery Person $2.740 \times 10 ^ { - 4 }$