Question 15704
If a 3-digit number (000 to 999) is chosen at random, find the probability that exactly one digit will be less than 2.
there are some things not clear ..a 3 digit number if you say ,it can be only 100 to 999 ,not 000 to 999..please check how/where you got the idea. any way i will give the method
total  3 digit numbers = 999-100+1 = 900
 now less than 2 we can have 1 or 0 . but in the first digit we can not have zero.hence numbers with 1 in the first digit can be 
 1(1st.digit)*8(second digit)*8(3rd.digit)= 64..(second & 3rd. digits will have to be between 2 and 9 ..that is 8 possibilities)
  Similarly with 1 or zero in the second digit we can have 
  8*2*8 = 128 
 Similarly with 1 or zero in the 3rd. digit we can have 
  8*8*2 = 128 
  so total possibilities =64+128+128=320
 probability =320/900 =32/90 =16/45