Answer:
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 .