Question

The Library of Congress, the largest library in the world have 25% of the books on Literature, 200 are on Fiction and rest are Novels. If the ratio of the number of books on Novel, Fiction and Literature is 5∶4∶3. How many new books on Literature are to be added to the Library collection to make the percentage of Literature as 40% ?
1. 78
2. 150
3. 100
4. 115

Answer 1

Correct Answer - Option 2 : 150

Given∶

 

In the Library, 25% of the books on Literature, 200 are on Fiction and rest are Novels.

Formula Used∶

Basics of Percentage, Ratios.

Calculation∶

By using basics Ratios concepts, the actual number of Novels, Fiction and Literature books may be assumed as 5x, 4x and 3x respectively with x as the common factor.

As number of Fiction books are 200, we can find the value of x easily,

4x = 200

x = 50

So, total number of books = 5x + 4x + 3x = 12x

Or, 12x = 12 × 50 = 600 and

Number of Literature books = 3x = 3 × 50 = 150

Assumed that number of Literature books to be purchased as y

So, 0.4(600 + y) = 150 + y

Or, 0.6y = 90

y = 150

∴ 150 new books of Literature are to be added to the Library collection.