You work as a health inspector and must visit each of the 15 restaurants in town once each week. a) In how many different orders can you make these inspections?
b) If you were to work 50 weeks a year and use a different order every week, how long would it take you to try all of the different possible orders

Step-by-step explanation:

The no of different ways in which these restaurants can be visited

= ¹⁵P₁₅

= 15 x 14 x 13 x 12 x 11 x 10 x 9 x 8 x 7 x 6 x 5 x 4 x 3 x 2 x 1

= 1.30 x 10¹²

b ) Each combination takes 1 week and 50 weeks in  a year to work

No of years to take to try all the combination

= 1.30 x 10¹² / 50

= 2.615 x 10¹⁰ years .

the mistake in the pattern is that :

b. the decimal point was moved one too many place values each time

the correct pattern could be made by :

b. moving the decimal point to the right the same numbers of place values as the exponents