Question

A teacher who teaches online at Lamamia wrote a 90
digit positive number 112222333333... in his laptop.
Then he inserted a three-digit number between any
two distinct digits. Now the new number cannot be
perfectly divisible by 11. Find the number of possible
values of three digit numbers.
(a) 819
(b) 781
(c) 881
(d) none of these​

Answer 1

Answer:

d none of these . this is the write

Answer 2

Answer:

(a) 819

Step-by-step explanation: If the three digit number is not divisible by 11,the new number cannot be divisible by 11

Total three digit numbers = (999-100)+1 =900

The 1st 3 digit number divisible by 11 is 110 and the last 3 digit number divisible by 11 is 990

Total three digit number divisible by 11 = [(990-110)/11]+1 = 81

Therefore the number of three digit numbers that cannot be divisible by 11 = 900-81 = 819