What is the fastest way to double your money?

I am sure no one can have two things for dinner. what are they?

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

'S' refers to the number of seconds in a day and 'H' refers to the number of hours in ten years. Which quantity out of these two is greater?

Can it be possible to build a house that has all its four walls facing towards the South?

A cricket has 6 legs, a squirrel has 4 legs and a spider has 8 legs.

In a local zoo, it was found that the total number of legs is 612. Also, there are equal number of each of the above animals/insects.

Can you find out how many animals are there in the zoo?

With the help clues provided in the image, can you find the 5 digit key?

What can run but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?

If,
9 * 8 * 7 = 65
8 * 7 * 6 = 50
7 * 6 * 5 = 37

Find
6 * 5 * 4 = ?

John can place six large boxes or nine small boxes into a carton.

Can you find out in how many cartons can he place sixty-six boxes in total?