What is the number of numbers that can be made from the numbers two and three such that the number contains 4 digits?

1 Answer
Feb 22, 2016

#2^4 =16#

Explanation:

There are #2# possibilities for the first digit (either two or three).
For each of those #2# possibilities there are #2# possibilities for the second digit for a combination of #2xx2=4# possibilities for the first two digits.
For each of those #4# possibilities there are #2# possibilities for the third digit, for a combination of #4xx2=8# possibilities for the first three digits.
For each of those #8# possibilities there are #2# possibilities for the four digit, for a combination of #8xx2=16# possibilities for the four digits.