The marks on a combination lock are numbered 0 to 39. If the lock is at mark 19, and the dial is turned one mark clockwise, it will be at mark 18. If the lock is at mark 19 and turned 137 marks clockwise, at what mark will it be

Mark 2

Step-by-step explanation:

There are 40 marks on the lock.

Every full turn of 40 marks, the lock will come back to mark 19.

137/40 = 3R17

You can make three full turns (which is equivalent to doing nothing), and then you must move 17 more marks.

19 - 17 = 2

The lock will be at mark 2.