Replace each alphabet with the number (1-9) to make the below equation correct.

AB * C = DE - F = GH / I

What is more useful when it is broken?

One day, John and his friends were playing around. Jacob hit something with a Pin and it popped. John's dad came into the room that very moment, but he wasn't mad. In fact, he was smiling. What did Jacob hit?

What goes up but never comes down?

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

Different lights make me strange by changing me into different sizes. What am I?

What does man love more than life, and hate more than death or mortal strife; that which satisfied men want; the poor have, and the rich require; the miser spends, the spendthrift saves, and all men carry to their graves?

All of you like to eat me. I am a five-lettered word. Remove the first two and I turn into an infamous animal. Remove just the first and I become a heinous crime. Remove the first and the last and you can groove on me.

Can you guess who am I?

If nine thousand, nine hundred nine dollars is written as $9,909,
how should twelve thousand, twelve hundred twelve dollars be written?

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?