Click to Chat
1800-1023-196
+91-120-4616500
CART 0
Use Coupon: CART20 and get 20% off on all online Study Material
Welcome User
OR
LOGIN
Complete Your Registration (Step 2 of 2 )
there are 8 railway stations along a rail line.in how many way can a train be stopped at 3 of these stations such that no two of them are consecutive?
Dear student, The required number of ways=8P3 Use permutation
Dear student,
The required number of ways=8P3
Use permutation
No.of ways to select 3 stations among 8 stations = 8C3No.of possibilities of 3stations might be consecutive = 6No.Of possibilities of 2 stations among those 3 might be consecutive = 30So, resultant answer is 8C3 - 6 - 30 = 20
Total No of way can a train be stopped= 8c3=42let those eight stations be {1 2 3 4 5 6 7 8}{(1,2)(2,3)(3,4)(4,5)(5,6)(6,7)(7,8)}7 {(1,2,3)(2,3,4)(3,4,5)(4,5,6)(5,6,7)(6,7,8)}No.Of waysof 2 stations among those 3 might be consecutive =6No.of ways of 3stations might be consecutive = therefore Ans is 42-(6+7)=20
Find solution of question on doubt solving app Instasolv
Post Question
Dear , Preparing for entrance exams? Register yourself for the free demo class from askiitians.
points won -