If you drop me I’m sure to crack, but give me a smile and I’ll always smile back. What am I?

Can you solve this picture maths equation?

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

John was a very careless driver, so his owner Jacob gave him an offer that he will get an incentive of Rs.30 for every bottle box he delivered without breaking it and he will be charged Rs.90 for every bottle box he broke. Jacob gave John 100 bottles-box to deliver. After delivery, Jacob paid John Rs.2400. How many bottles-box did John break?

Spot 5 differences in two Christmas tree below:

We are a group of eight brothers. We consider the weak, yet we protect the king in every battle. If we move ahead, we never turn back. Who are we?

If eleven plus two equals one, what does nine plus five equal?

A Shopkeeper collects 71 rupees in the form of 20 paisa and 25 paisa.
He collects a total of 324 coins.

Can you tell me how many number of 20-paisa and 25-paisa he got?

We know that the number 7 is the prime followed by a cube. Which next number is also a prime followed by a cube?

I am eight letters long - "12345678"
My 1234 is an atmospheric condition.
My 34567 supports a plant.
My 4567 is too appropriate.
My 45 is a friendly thank-you.
My 678 is a man's name.

What word am I?