in a library there are 1500 books . Among these books the ratio of books about science and commerce is 1:2 . Determine the number of books about science is to be purchased so that this ratio becaume 3:5
Answers
Answer: 100 science book needs to be purchaesd
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Answer:
Number of Science books purchased is 100 so that new ratio becomes 3 : 5
Step-by-step explanation:
Given :
No. of books in a library =1500
Ratio of books of Science to Commerce =1 : 2
Sum of ratio = 1 + 2=3
No. of Science books in the library = (part of science book / sum of ratio )× total books in the library
= ( 1 /3 ) × 1500
= 500 books
No. of Commerce books in the library = (part of commerce books / sum of ratio ) × total no. of books in the library
=(2 / 3 ) × 1500
= 1000 books
Let no. of Science books purchased = x
Now no. of Science books = 500 + x
No. of Commerce books remains same
New ratio of no. of Science books to Commerce books= (500 +x) : 1000
According to question ,this ratio is 3 : 5
So, 3 : 5 =(500 +x) : 1000
3 / 5 = (500 + x) / 1000
By doing cross multiplication,
5 (500 +x ) = 3× 1000
2500 + 5x = 3000
5x = 3000 - 2500
x = 500 / 5
x = 100