A bag contains 64 balls of eight different colours. There are eight of each colour (including red). What is the least number you would have to pick, without looking, to be sure of selecting 3 red balls?

I have two sand hourglasses:
1. A 7 minute one and
2. An 11-minute one.

Using just these 2 sand hourglasses, how can I measure time as 15 minutes?

In The Image Below Which clock is the odd one out?

How many times in a given day, minutes and hour clock comes in a straight line ?

I always drive my customer away.

Who am I?

Which digit occurred maximum times between the number 1 and 1000?

I have a sore throat and a severe headache. I have four tablets with me that are identical to each other and they do not have any cover on them. There is no way I can identify which tablet serves what purpose. The only thing that I know is that two of these four tablets are for the throat and the remaining two are for the headache. To treat my condition, I must take 1 of each. What will I do now?

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?

Three people check into a hotel. They pay $60 for the rent of the room. After they check-in, the manager realize that the rent for the room is $55. So, he gives $5 to the bellboy and asks him to give it to them. The bellboy thinks that it will be difficult for the three people to share $5 among them and seeking the personal benefit, he pockets $2 and gives the remaining $3 to them.

Now, each person paid $20 and got back $1. In this manner, each of them paid just $19 which totals to the amount of $57. The bellboy has $2 with him and adding them, we get $59. So where is the remaining $1?

The day before yesterday I was 25 and the next year I will be 28. This is true only one day in a year. What day is my birthday?