If I write one digit per second, how long will it take me to write out all the numbers from 1 to 1989?

Question

If I write one digit per second, how long will it take me to write out all the numbers from 1 to 1989?
 
a. 33 min 9s

b. 1 h 22 min 39s

c. 1 h 54 min

d. 1 h 54 min 9s

 

 

 

Answer 1

The answer is D.  First, you need to determine how many characters each number has.  For the numbers 1-9, there is 1 digit each.  Multiply 1 times the number of "numbers, which is.  9 numbers all with 1 digit each.  Then look at the numbers 10-99.  You have 90 numbers with 2 digits each, so that gives you 18 digits total.  SO on and so forth.  Then , you add all those digit up and that gives you 6,849 digits. One digit per second means it will take 6,849 seconds.  Now convert that into minutes, then hours, and that gives you your answer.