Question

A girl can finish reading a book in 15 days if she reads 10 pages of it every day. The number of days she will take to finish it, if she reads 25 pages every day, is?​

Answer 1

Given :

• A girl can finish reading a book in 15 days if she reads 10 pages of it every day

To find :

• The number of days she will take to finish it, if she reads 25 pages every day

Solution :

Here we use the concept of Unitary Method. First we will find the the time taken by the girl to finish the book if she reads 1 page/day and then we can divide it by 25.

★ Number of days taken to finish the book if:-

→ She reads 1 page every day = 15 × 10

→ She reads 1 page every day = 150 days

★ Number of days taken to finish the book if:-

→ She reads 25 pages every day = 150/25

→ She reads 25 pages every day = 6 days

Answer :

• The required answer = 6 days

Answer 2

Given :

A girl can finish reading a book in 15 days if she reads 10 pages of it every day

To find :

The number of days she will take to finish it, if she reads 25 pages every day

Solution :

Here we use the concept of Unitary Method. First we will find the the time taken by the girl to finish the book if she reads 1 page/day and then we can divide it by 25.

★ Number of days taken to finish the book if:-

→ She reads 1 page every day = 15 × 10

→ She reads 1 page every day = 150 days

★ Number of days taken to finish the book if:-

→ She reads 25 pages every day = 150/25

→ She reads 25 pages every day = 6 days

Answer :

The required answer = 6 days

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