Why do we preferably have round manhole covers and not square ones?

You have two buckets - one holds exactly 5 gallons and the other 3 gallons. How can you measure 4 gallons of water into the 5 gallon bucket?

(Assume you have an unlimited supply of water and that there are no measurement markings of any kind on the buckets.)

When I asked a girl's name she told me her name is the date '07/09/2001'.

I thought for a few seconds and then I got her name. Do you?

Doctor Alex and a bus driver John are both in love with the same woman named Olivia. The bus driver need to go for a long trip of 10 days, Before he left he gave Olivia 10 apples.

What does man love more than life, hate more than death or mortal strife; That which contented men desire; the poor have, the rich require; the miser spends, the spendthrift saves, and all men carry to their graves?

How can you take 2 from 5 and leave 4?

The centre of the third figure is empty. What digit should fit inside?

using four eights (8) and a one (1) and one mathematical symbol , create the number 100

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?