Question

58
EXEMPLAR PROBLEMS
10. The students of a school decided to beautify the school on the Annual Day by
fixing colourful flags on the straight passage of the school. They have 27 flags
to be fixed at intervals of every 2 m. The flags are stored at the position of the
middle most flag. Ruchi was given the responsibility of placing the flags. Ruchi
kept her books where the flags were stored. She could carry only one flag at a
time. How much distance did she cover in completing this job and returning
back to collect her books? What is the maximum distance she travelled carrying
a flag?​

Answer 1

Answer:

◆ It is given that there are 27 flags all are kept at the place where the middle flag is posted (O)

And ruchi kept her book there

◆ So, we have to find the total distance travelled by ruchi to post all the flags from (O) which are 2m apart from each other.

◆So, we found the middle flag where ruchi kept her book(O) as 14.

◆ So, there are 13 flags on both the sides of (O).

◆ Let's find the distance travelled by ruchi on one side of middle flag suppose from 'O' to 'A'

◆ As, she have to travel again after posting one flag to position 'O'

So, we found as a1 = 4, a2= 8 ,a3= 12.........

Therefore they are in A.P since we got the difference d = 4.

◆ Now , we found the distance coved by ruchi for posting 13 flags from 'O' to 'A' as 364m.

◆ So, she also travelled 364 m on other side of the middle flag (OB).

◆ There fore, the total distance travelled by ruchi for posting 27 flags is 2×364 = 728 m.

ANS = 728 m.