CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

10x when divided by 13 remainder = -1. If x is a natural number less than 100 how many solutions are possible for x ?
  1. 33
  2. 21
  3. 17
  4. 16
  5. None of these


Solution

The correct option is C 17

The first power of 10 for which a division by 13 gives a remainder -1 is x=3. the next power of 10 will be 109. hence it falls in an AP with first term as 3 and last term as 99 with a common difference of 6

number of terms = (99-3)/6 +1= 96/6 +1 = 16 +1 = 17 terms. 

flag
 Suggest corrections
thumbs-up
 
0 Upvotes



footer-image