Question

Probability that number between 100 and 999 does not contain digit 7

Answer 1

Answer:

0.63

Step-by-step explanation:

Number of numbers between 100 and 999 = 900

The digits that contain 7 between 100 and 999:

Between 100 and 200:

{107, 117, 127, 137, 147, 157, 167, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 187, 197} = 19

Similarly, between 201 and 300 = 19

Similarly, between 301 and 400 = 19

Similarly, between 401 and 500 = 19

Similarly, between 501 and 600 = 19

Similarly, between 601 and 700 = 20(include 700)

Between 701 and 800 = 99

Between 801 and 900 = 19

Total number of possibilities of numbers that contains the number ‘7’ = 19 + 19 + 19 + 19 + 19 + 20 + 99 + 19

                = 233

The numbers that don’t contain 7 = 900 — 233 = 567

Therefore, the probability that numbers between 100 and 999 does not contain digit 7 = The possibility that numbers don’t contain 7 / Total number of possibilities

                                            = 567 / 900 = 63 / 100 = 0.63