Try it on paper first. A hint, the key idea and the worked solution are here when you need them.
Kabir opens a safe. He turns its dial clockwise through full turns and then more. Then he turns it anticlockwise through one and a half turns. Write each turn as an angle with its sign. What is the total angle, and which angle from to ends in the same place?
An angle is a turn from the initial side to the terminal side: anticlockwise is positive, clockwise is negative. One revolution is . Angles that differ by a multiple of end in the same place (they are coterminal). and .
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. The first turn. Clockwise, so it is negative: .
Step 2. The second turn. One and a half turns anticlockwise: .
Step 3. The total. .
Step 4. The same end. .
Answer: the turns are and ; the total is , which ends like .
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