# All Puzzles

• John has sons.
His eldest son is four years older than his second son.
The second son is four years older than the youngest son.
The youngest son is exactly half the age of the eldest.
What are the sons’ ages?

View Solution
Submit Solution
pnikam Expert
• 1,433.2K views

• A lilypad doubles in size each day.
In 28 days, the lilypad will cover the entire pond.

In how many days will the pond be half covered?

View Solution
Submit Solution
pnikam Expert
• 1,434.0K views

• A man spends one fifth of the money in his wallet.
He then spends one fifth of what remains in the wallet.
He spends \$36.00 in all.
How much money did he have to begin with?

View Solution
Submit Solution
pnikam Expert
• 1,435.7K views

• All students in the physics class also study mathematics. Half of those who study literature also study mathematics. Half of the students in the mathematics class study physics. Thirty students study literature and twenty study physics. Nobody who studies literature studies physics. How many students in the mathematics class study neither physics nor literature?

View Solution
Submit Solution
pnikam Expert
• 1,434.2K views

• Mathematical aptitude tests frequently have sets of numbers where you are supposed to figure out a pattern or guess the next number. For example,

• (2, 4, 6, 8, 10)  is a list of even numbers corresponding to 2×n  for n=1, 2, 3, …

• (1, 1, 2, 3, 5)  is the well-known Fibonacci series where two adjacent numbers are added to produce the next number.

• (2, 3, 5, 7, 11)  is a list of prime numbers.

• (1, 2, 4, 8, 16)  is an exponential series corresponding to 2n  for n=0, 1, 2, …

Can you figure out the special significance of the following sequence?
(2, 6, 10, 15, 19

View Solution
Submit Solution
pnikam Expert
• 1,434.7K views

• The Bermuda Triangle is a place in the Atlantic Ocean where ships and airplanes supposedly disappear without a trace. In the picture below, a square appears when we rearrange the pieces of the upper triangle to form the lower triangle. The pieces in both pictures are identical. Can you explain the origin of the square? You will need your knowledge of geometry to solve this problem.

View Solution
Submit Solution
pnikam Expert
• 1,449.1K views

• A chicken farmer has figured out that a hen and a half can lay an egg and a half in a day and a half. How many hens does the farmer need to produce one dozen eggs in six days?

View Solution
Submit Solution
pnikam Expert
• 1,435.7K views

• Three students checked into a hotel and paid the clerk \$30 for a room (\$10 each). When the hotel manager returned, he noticed that the clerk had incorrectly charged \$30 instead of \$25 for the room. The manager told the clerk to return \$5 to the students. The clerk, knowing that the students would not be able to divide \$5 evenly, decided to keep \$2 and to give them only \$3.

The students were very happy because they paid only \$27 for the room (\$9 each). However, if they paid \$27 and the clerk kept \$2, that adds up to \$29. What happened to the other Dollar?

View Solution
Submit Solution
pnikam Expert
• 1,448.2K views

• There are twelve identical-looking balls, but one is either heavier or lighter than the other eleven. How can you determine which is the odd ball and find out whether this ball is heavier or lighter than the others using only three weighings with a balance?

View Solution
Submit Solution
pnikam Expert
• 1,434.2K views