Question

2. Salvador has 10 cards, each with one number on

it. The numbers are 2, 3, 4,5,5,7,7,7,7,7.
Salvador is going to make a row containing all 10
cards. How many ways can he order the row?

Answer 1

15,120 number of ways.

Explanation:

This is a permutation problem. Given the 10 cards with numbers 2, 3, 4,5,5,7,7,7,7,7 on it, if Salvador is going to make a row call, the number of ways he can order a row is as shown below;

Total number of cards = 10!

number of times the digit 5 was repeated = 2times

number of times the digit 7 was repeated = 5times

The number of ways he can make a row call = 10!/2!5!

= 10*9*8*7*6*5!/2*5!

= 10*9*8*7*6/2

= 10*9*8*7*3

= 15,120 different ways

Hence, the number of ways he can order the row is 15,120 number of ways.