AGE AND BIRTHDAY RIDDLES WITH ANSWERS TO SOLVE - PUZZLES & BRAIN TEASERS

May the Fourth (be with you!) Did you answer this riddle correctly?
YES  NO  

Mark's mom said, "Your father, grandfather, and great grandfather were all born in January. You were born in July." Did you answer this riddle correctly?
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Only twenty-three people need be in the room, a surprisingly small number. The probability that there will not be two matching birthdays is then, ignoring leap years, 365x364x363x...x343/365 over 23 which is approximately 0.493. this is less than half, and therefore the probability that a pair occurs is greater than 50-50. With as few as fourteen people in the room the chances are better than 50-50 that a pair will have birthdays on the same day or on consecutive days. Did you answer this riddle correctly?
YES  NO  

Billie lives in the southern hemisphere. Did you answer this riddle correctly?
YES  NO  

A teenager! Did you answer this riddle correctly?
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This one is best solved working backwards, the last part David spent half of what was left plus $1.00 on candy and then was out of money. That means he must have spent $2.00 on Candy as $1.00 was half of what he had using the same logic backwards: $2.00 on candy $6.00 on Balloons and Streamers $12.00 on the cake Total of $20.00. Did you answer this riddle correctly?
YES  NO  

A tree Did you answer this riddle correctly?
YES  NO  

I'm a tree. Did you answer this riddle correctly?
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Goateneye. Did you answer this riddle correctly?
YES  NO  

Malcolm is 6.
The father is 42. 42 days = 6 weeks.
The grandfather is 72. 72 months = 6 years. Did you answer this riddle correctly?
YES  NO  

Freeze a jolly good fellow Did you answer this riddle correctly?
YES  NO  

Because there were so many knights! Did you answer this riddle correctly?
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Current Future Past

Princess x 2z (x+y)/2
Prince y x z

I then created three equations, since the difference in their age will always be the same.

d = the difference in ages

x y = d
2z x = d
x/2 + y/2 z = d

I then created a matrix and solved it using row reduction.

x y z

1 -1 0 d
-1 0 2 d
.5 .5 -1 d

It reduced to:

x y z

1 0 0 4d
0 1 0 3d
0 0 1 5d/2

This means that you can pick any difference you want (an even one presumably because you want integer ages).

Princess age: 4d
Prince age: 3d

Ages that work

Princess:
4
8
16
24
32
40
48
56
64
72
80

Prince:
3
6
12
18
24
30
36
42
48
54
60 Did you answer this riddle correctly?
YES  NO  

Knight-time. Did you answer this riddle correctly?
YES  NO  

3, 3, and 8. The only groups of 3 factors of 72 to have non-unique sums are 2 6 6 and 3 3 8 (with a sum of 14). The rest have unique sums:

2 + 2 + 18 = 22
2 + 3 + 12 = 18
2 + 4 + 9 = 15
3 + 4 + 6 = 13

The house number alone would have identified any of these groups. Since more information was required, we know the sum left the answer unknown. The presence of a single oldest child eliminates 2 6 6, leaving 3 3 8 as the only possible answer. Did you answer this riddle correctly?
YES  NO