One is to three as three is to five and five is to four and four is the magic number.
What is the pattern?

An exterior architect is asked by a builder to plant seven trees in a manner that there are exactly six rows of trees in a straight line and each row has three trees in particular.

How will he do it?

Only one color, but not one size,
Stuck at the bottom, yet easily flies.
Present in sun, but not in rain,
Doing no harm, and feeling no pain.
What is it?

Prove that twice of ten is the same as twice of eleven.

Replace each alphabet with the number (1-9) to make the below equation correct.

AB * C = DE - F = GH / I

Three doctors said that Bill was their brother. Bill says he has no brothers. How many brothers does Bill actually have?

Can you divide the below-given shape into four equal and identical pieces?

A prisoner is told: "If you tell a lie, we will hang you and if you tell the truth, we will shoot you." What did the prisoner say to save himself?

Four men were in a boat on the lake. The boat turns over, and all four men sink to the bottom of the lake, yet not a single man got wet! Why?

When I get multiplied by any number, the sum of the figures in the product is always me. What am I?