Cristina was born in 1888. She just had her 30th birthday today how did that happen?

I am a type of vehicle that has two wheels and is powered by humans. What am I?
Hint 1: You can ride me for exercise.
Hint 2: I am environment-friendly.

A frog is at the bottom of a 30-meter well. Each day he summons enough energy for one 3-meter leap up the well. Exhausted, he then hangs there for the rest of the day. At night, while he is asleep, he slips 2 meters backwards. How many days does it take him to escape from the well?

Why is 6 afraid of 7?

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

Solve the counting riddle by identifying the number of triangles in the given picture.

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

Two old friends, Jack and Jill, meet after a long time, and discussing as:

Jack: Hey, how are you, man?

Bill: Not bad, got married and I have three kids now.

Jack: That's awesome. How old are they?

Bill: The product of their ages is 72 and the sum of their ages is the same as your birth date.

Jack: Cool..But I still don't know.

Bill: My eldest kid just started taking piano lessons.

Jack: Oh, now I get it.

How old are Bill's kids?

Using eight eights and addition only, can you make 1000?

Can you solve the below tricky visual equation?