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A school has three gates and four staircases from the first floor to the second floor. How many ways does a student have to go from outside the school to his classroom on the second floor?

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Question

A school has three gates and four staircases from the first floor to the second floor. How many ways does a student have to go from outside the school to his classroom on the second floor?

Sum
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Solution

3 gates to enter the school.

4 staircases to go from the first floor to the second floor.

∴ the number of ways of going to the classroom is

`=(("The number of ways"),("to enter the school")) xx (("The number of ways to"),("go to the second floor"))`

= 3 × 4

= 12 ways

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Chapter 3: Permutations and Combination - Exercise 3.1 [Page 48]

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