I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

O_er_t_o_

Complete the missing letters of the given word.

Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

In case you were starting to feel confident, this one was meant for third graders in Vietnam. The answer is 66, but we don't blame you for scratching your head about how they got there.

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?

A word I know,
Six letters contain,
Subtract just one,
And twelve is what remains.

A pet show was happening in my locality. I went down along with my kids. In that show, I noticed that all except two of the entries were cats. All except two were dogs and all except two were Monkeys.

Can you find out how many of each animals were present in that pet show?

If six children and two dogs were under an umbrella, how come none of them got wet?

Can you find the least possible number such that

If the number is divided by 3, it gives the remainder of 1;
If the number is divided by 4, it gives the remainder of 2;
If the number is divided by 5, it gives the remainder of 3;
If the number is divided by 6, it gives the remainder of 4.

How can you leave a room with two legs and return with six legs?