Latest Elitmus Aptitude Question SOLUTION: sherlock homes and dr. watson have to travel from rajiv gandhi chowk to indira gandhi internation airport via the metro they have enough coins of 1,5,10,25 pasie.shelock homes agr

Ans=49
1p 25p 1
1p 5p 9
1p 10p 4
5p 10p 4
5p 25p 1
1p 5p 10p 4+3+3+2+2+1+1=16
1p 5p 25p 4
1p 10p 25p 2
5p 10p 25p 2
1p 10p 25p 5p 2
1p 1
5p 1
10p 1
25p 1

Arrange the combinations of the coins in the decreasing order of denominations :
Case 1: when there is 2 25pc coin - 1 ways
Case 2: when there is 1 25pc coin and
(1) 2 10pc coin - nos of 5pc coin will range from 1 to 0 i.e 2 combinations
(2) 1 10pc coin - nos of 5pc coin will range from 3 to 0 i.e 4 combinations
(3) 0 10pc coin - nos of 5pc coin will range from 5 to 0 i.e 6 combinations
Case 3: when there is no 25 pc coins and
(1) 5 10pc coin - 1 ways
(2) 4 10pc coin - nos of 5pc coin will range from 2 to 0 i.e 3 combinations
(3) 3 10pc coin - nos of 5pc coin will range from 4 to 0 i.e 5 combinations
(4) 2 10pc coin - nos of 5pc coin will range from 6 to 0 i.e 7 combinations
(5) 1 10pc coin - nos of 5pc coin will range from 8 to 0 i.e 9 combinations
(6) 0 10pc coin - nos of 5pc coin will range from 10 to 0 i.e 11 combinations
So a total 49 different combinations.





q2


Again arrange the coins in decreasing order of denominations:

Case 1: when there is 1 25pc coin and
(1) 2 10pc coin - 1 ways
(2) 1 10pc coin - nos of 5pc coin will range from 2 to 0 i.e 3 combinations
(3) 0 10pc coin - nos of 5pc coin will range from 4 to 0 i.e 5 combinations

Case 3: when there is no 25 pc coins and
(1) 4 10pc coin - nos of 5pc coin will range from 1 to 0 i.e 2 combinations
(2) 3 10pc coin - nos of 5pc coin will range from 3 to 0 i.e 4 combinations
(3) 2 10pc coin - nos of 5pc coin will range from 5 to 0 i.e 6 combinations
(4) 1 10pc coin - nos of 5pc coin will range from 7 to 0 i.e 8 combinations
(5) 0 10pc coin - nos of 5pc coin will range from 9 to 0 i.e 10 combinations

So total different combinations = 39

let us make possible combination
ans=49
possible combination-
coins used total possible combinations
1p 25p- 1
1p 5p 9
1p 10p 4
5p 10p 4
5p 25p 1
1p 5p 10p 4+3+3+2+2+1+1=16
1p 5p 25p 5
1p 10p 25p 2
5p 10p 25p 2
1p 10p 25p 5p 1
1p 1
5p 1
10p 1
25p 1

Can anyone please explain it in a better way with a better explanation?

49 is not in the option

let us make possible combination
ans=49
possible combination-
coins used total possible combinations
1p 25p- 1
1p 5p 9
1p 10p 4
5p 10p 4
5p 25p 1
1p 5p 10p 4+3+3+2+2+1+1=16
1p 5p 25p 5
1p 10p 25p 2
5p 10p 25p 2
1p 10p 25p 5p 1
1p 1
5p 1
10p 1
25p 1


hence adding all we have 49 combinations

Could any one explain how this question solved? I am not getting how combination made.

answer of second question is 39