Exercise 1.3. a telephone number consists of ten digits, of which the first digit is one of 1; 2; : : : ; 9 and the others can be 0; 1; 2; : : : ; 9. what is the probability that 0/ appears at most once in a telephone number, if all the digits are chosen completely at random

The probability that "0" appears at most once in a telephone number is 0.82

Step-by-step explanation:

Telephone number = 10 digits

First digit = (1,2......9)------> there are 9 possible digits

digit 2 - digit 10 = (0,1,2......9) -----> there are 10 possible digits

Let's find the total amount of telefone numbers with those characteristics:

possible first digit X possible second digit X...............X possible tenth digit

9X10X10X10X10X10X10X10X10X10 =

Let's find the amount of telephone numbers that "0" appears at most once (it means 0 will occur either once or will not occur):

If "0" appears once, the rest of the numbers should be 1.2.....9 (9 possible digits)

9X10X9X9X9X9X9X9X9X9 =

If "0" doesn't appear, the ten digits should be 1,2....9

9X9X9X9X9X9X9X9X9X9 =

Finally, find the probability

P=(favorable outcomes/total outcomes)

P= = 0.82

answer: 5100 just subtract

step-by-step explanation:

think about the doctor who treated the major and the speaker in the short story "in another country." put yourself in the shoes of the doctor, and based on what you read in the story, write what you think his thoughts about the major and the speaker would be. use the following vocabulary in your response and change the form of these words as needed: detached resign withered