Question

how many 4 digit number can be formed using a digit 0,1,2,3,4,5 divisible by 8
(I) repetition not allowed
(ii) repetition is allowed
​

Answer 1

Answer:

37

Step-by-step explanation:

The correct option is D 37

Any number is divisible by 8 if last three digit is divisible by 8

024,032,104,120,152,240,304,312,320,352,432,504,512,520

Case 1: when last three digit contains 0,

total 9 cases will there and thousands place can be filled in 3 ways 

Case 2: when last three digit does not contains 0,

total 5 cases will there and thousands place can be filled in 2 ways 

Total required numbers=9×3+5×2=37