Maths problems (interesting ones)

[Dave Scheck]

6) (9*9) + 9 + 9 + (9/9) = 100

(9*9) = 81
81 + 9 = 90
90 + 9 = 90
99 + (9/9) = 99 + 1 = 100

7) It will take him 12 days

Day 1  :  Start - 0 After Climb - 4   After Sleep - 1
Day 2  :  Start - 0 After Climb - 5   After Sleep - 2
Day 3  :  Start - 0 After Climb - 6   After Sleep - 3
Day 4  :  Start - 0 After Climb - 7   After Sleep - 4
Day 5  :  Start - 0 After Climb - 8   After Sleep - 5
Day 6  :  Start - 0 After Climb - 9   After Sleep - 6
Day 7  :  Start - 0 After Climb - 10  After Sleep - 7
Day 8  :  Start - 0 After Climb - 11  After Sleep - 8
Day 9  :  Start - 0 After Climb - 12  After Sleep - 9
Day 10 :  Start - 0 After Climb - 13  After Sleep - 10
Day 11 :  Start - 0 After Climb - 14  After Sleep - 11
Day 12 :  Start - 0 After Climb - 15 
(There must be some sort of equation, it's escaping me right now)

8) Well, if you take it as an independent case, it's like a coin. It's either a boy or a girl; 50/50. If you take genetics into acount, then if I remember right, there's a slightly better chance of it being a girl.