Riddles and Brain Teasers

Julian and Penelope’s Marriage Ages

When Julian and Penelope met, one was half the others age plus seven years. Ten years later when they married, Penelope was thirty, but this time one was nine tenths the age of the other. How old was Julian? (No fractions or partial years, whole numbers only).

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Julian was 27 when Penelope was 30.

Posted in Brain Teasers

Four Weights To Thirty

What four weights can be used to balance from one to thirty pounds?

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A = 1
B = 3
C = 9
D = 171 lb = A
2 lbs + A = B
3 lbs = B
4 lbs = A + B
5 lbs + A + B = C
6 lbs + B = C
7 lbs + B = A + C
8 lbs + A = C
9 lbs = C
10 lbs = A + C
11 lbs + A = B + C
12 lbs = B + C
13 lbs = A + B + C
14 lbs + B = D
15 lbs + B = A + D
16 lbs + A = D
17 lbs = D
18 lbs = A + D
19 lbs + A = B + D
20 lbs = B + D
21 lbs = A + B + D
22 lbs + A + B = C + D
23 lbs + B = C + D
24 lbs + B = A + C + D
25 lbs + A = C + D
26 lbs = C + D
27 lbs = A + C + D
28 lbs + A = B + C + D
29 lbs = B + C + D
30 lbs = A + B + C + D

A = 1
B = 3
C = 9
D = 17

1 lb = A
2 lbs + A = B
3 lbs = B
4 lbs = A + B
5 lbs + A + B = C
6 lbs + B = C
7 lbs + B = A + C
8 lbs + A = C
9 lbs = C
10 lbs = A + C
11 lbs + A = B + C
12 lbs = B + C
13 lbs = A + B + C
14 lbs + B = D
15 lbs + B = A + D
16 lbs + A = D
17 lbs = D
18 lbs = A + D
19 lbs + A = B + D
20 lbs = B + D
21 lbs = A + B + D
22 lbs + A + B = C + D
23 lbs + B = C + D
24 lbs + B = A + C + D
25 lbs + A = C + D
26 lbs = C + D
27 lbs = A + C + D
28 lbs + A = B + C + D
29 lbs = B + C + D
30 lbs = A + B + C + D

Posted in Brain Teasers

Train From Chicago to LA

An electric train is traveling on a 2000-mile journey from Chicago, IL to Los Angeles, CA. It has 16 cars with a total of 320 passengers. The weather is cloudy and cool, with a warm front approaching from the south. Which direction will the steam blow?

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There is no steam. It’s an electric train.

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