Martha types a 4−digit code into a keypad to unlock her car doors. The code uses the numbers 1 and 0. If the digits are selected

Question

Artist 52 [7]

4 years ago

10

Martha types a 4−digit code into a keypad to unlock her car doors. The code uses the numbers 1 and 0. If the digits are selected

at random, what is the probability of getting a code with exactly one 1? Enter your answer as a simplified fraction.

Mathematics

1 answer:

mr_godi [17] · Answer 1 · 2021-12-24T13:48:13+03:00

mr_godi [17]4 years ago

4 0

4 binary digits have 2^4 = 16 combinations.
The combinations with exactly one 1 are: 1000, 0100, 0010 and 0001. So 4 out of 16 codes have exactly one 1.

The chances of that are 4/16 = 1/4.