Total number of ways four people line up in the straight line with the given condition is equal to 18 ways.
As given in the question,
Total number of people = 4
Given condition :
First position can not occupied by youngest person:
First position occupied in 3 ways
Second position occupied in 3 ways
Third position occupied in 2 ways
fourth position occupied in 1 ways
Total number of ways = 3 × 3 × 2 × 1
= 18 ways
Therefore, the number of ways four people stand in straight line is equal to 18 ways.
Learn more about ways here
brainly.com/question/11823283
#SPJ4
