There are 70,674 3's in the first million digits of pi.
* * * * *
There are 100,230 3s and 100,106 9s.
Since the decimal representation of pi is essentially random, the number of times any digit appears should be approximately 10% of the total number of digits. So, for a million digits, there should be around 100,000 of any digit so it should have been immediately apparent that the previous answer was extremely unlikely. In fact it was incorrect to a very large degree!
28 3s
How many 3s are in 15
9
4
16
37.6666667
Pi is irrational. This means that as the extent of this number is infinite, therefore any numbers present in this number for an unspecified amount of time are also considered infinite. However, this is not necessarily the case. Consider that pi could go on forever, but after the billionth digit, for example, there would be no 3's.This could easily be the case, but we would never know for certain, because it doesn't matter how many digits we discover not to be 3's, the next digit could always be any number, including a 3.However, there are exactly digits, and provided these digits are positioned randomly throughout the number, (which is what irrational means) there is a 1 in 10 chance of the next digit being a 3. This also means that in any given sample of consecutive digits of pi, 1/10 of the digits are likely to be a 3. The bigger the sample, the closer to 10% that the number of 3's will be. So if we take a million digits of pi, we can estimate that approximately 100,000 of them would be 3's. We can check this estimate by looking at how many threes there really are: 100,230 3's according to various sources.
2,560
0
3000/3 = 1000
There are: 21/3 = 7
24 of them