In a garden, there are 10 rows and 12 columns of mango trees. The distance between the two trees is 2 metres and a distance of one metre is left from all sides of the boundary of the garden. The length of the garden is

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Question: In a garden, there are 10 rows and 12 columns of mango trees. The distance between the two trees is 2 metres and a distance of one metre is left from all sides of the boundary of the garden. The length of the garden is
[A].

20 m

[B].

22 m

[C].

24 m

[D].

26 m

Answer: Option C

Explanation:

Each row contains 12 plants.

There are 11 gapes between the two corner trees (11 x 2) metres and 1 metre on each side is left.

Therefore Length = (22 + 2) m = 24 m.

A printer numbers the pages of a book starting with 1 and uses 3189 digits in all. How many pages does the book have ?

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Question: A printer numbers the pages of a book starting with 1 and uses 3189 digits in all. How many pages does the book have ?
[A].

1000

[B].

1074

[C].

1075

[D].

1080

Answer: Option B

Explanation:

No. of digits in 1-digit page nos. = 1×9 = 9.

No. of digits in 2-digit page nos. = 2 x 90 = 180.

No. of digits in 3-digit page nos. = 3 x 900 = 2700.

No. of digits in 4-digit page nos. = 3189 – (9 + 180 + 2700) = 3189 – 2889 = 300.

Therefore No. of pages with 4-digit page nos. = (300/4) = 75.

Hence, total number of pages = (999 + 75) = 1074.