There is a box full of marbles,
all but two are blue,
all but two are green,
and all but two are red.

How many marbles are in the box?

A new Engineering building containing 100 offices had just been completed. John was hired to paint the numbers 1 to 100 on the doors. How many times will John have to paint the number nine (9)?

What has many keys but can’t open a single lock?

You are given four results as below:
1111 = F
2222 = E
3333 = T
Then, can you find out how to code 4444?

As a whole I am both
safe and secure.

Behead me and I become
a place of meeting.

Behead me again and I am
the partner of ready.

Restore me, and I become
the domain of beasts.

What am I?

In the addition below, all digits have been replaced by letters. Equal letters represent equal digits and different letters represent different digits.
ABCABA
BBDCAA
ABEABB
ABDBAA
------- +
AAFGBDH
What does the complete addition look like in digits?

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?

Take 9 from 6, 10 from 9, 50 from 40, and leave 6.

How Come ??

Analyze and find the missing item in the sequence:
16, 06, 68, 88, __, 98

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.