The meeting is only for parents so total parents = 3 + 3 = 6

No. of seats available = 9 excluding teacher

total number of people = 7 children + 1 mother

half of them = 8/2 = 4

so, total no. of boys =4

The victim got injured on his right side so the murderer should be a leftie.

1. The man at counter giving money by his right hand so he cannot be the murderer.
2. The man who is checking clothes is a leftie so he may be the murderer.

Total Money Sasha gets by dividends = 2000+ 4000+6000+6000+5000 = 23000

Therefore Sasha gets extra 3000 by investing in the company.

Bank :

1. Simple interest :
20,000 * 5*r/100   < 3000

therefore r < 3

2. If Compound interest :

20,000 ((1+r/100)^5 -1) < 3000

therefore r < 2.83

Alive = Dead     so it is also possible that Dead  = Alive

1. Fred will be alive
2. then Fred will be dead after bob wish.
3. Then Fred and bob will be alive after john wish as dead means alive now.

So Finally all three are alive.

Ans : 3, It is following binary digit system.

2^0 = 1
2^1 = 2
2^2 = 4
2^0 + 2^ 1 = 3