John is the son of Jacob.
So,
Jacob is the_____of John's father?

There are 2 people near the river and both of them want to get on the other side. The boat can only take one of them. But they got across.
How?

Can you spot the man between the coffee bean in the picture below ?

I have branches, but no fruit, trunk or leaves. What am I?

Replace the question mark with the correct number in below Picture:

What is the word or phrase?

The day after tomorrow will be three days before Tuesday. Can you find out what is today?

We have arranged an array of numbers below. What you have to do is use any kind of mathematical symbol you know excluding any symbol that contains a number like cube root. You can use any amount of symbols but you have to come up with a valid equation for all of them.

0 0 0 = 6
1 1 1 = 6
2 + 2 + 2 = 6
3 3 3 = 6
4 4 4 = 6
5 5 5 = 6
6 6 6 = 6
7 7 7 = 6
8 8 8 = 6
9 9 9 = 6

It is deaf, Dumb and Blind!!!

Still, always tells the truth. What is it?

A brand new Mobile Phone was on sale at 20% as a promotional offer. By what per cent must the Mobile price be increased to sell it at the original price again?