Answer:The height of the building which caste a shadow 20.5 m in length is 17.5 m.
Step-by-step explanation:
Given : At a particular time of a day, a 7 high flagstaff castes a shadow which is 8.2 m long.
To find : What is the height of the building which castes a shadow 20.5 meters in length at the same moment?
Solution :
A 7 high flagstaff castes a shadow which is 8.2 m long.
i.e. Shadow of length 8.2 m = 7 m
The shadow of length 1 m = m
The shadow of length 20.5 m = m
The shadow of length 20.5 m = 17.5 m
Therefore, The height of the building which caste a shadow 20.5 m in length is 17.5 m.
