SOLUTION: Ratio of english books to maths books is 3:5.If the number of english books is 630 find the total number of books

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Question 847471: Ratio of english books to maths books is 3:5.If the number of english books is 630 find the total number of books
Answer by swincher4391(1107) About Me  (Show Source):
You can put this solution on YOUR website!
English : Math - > 3:5
Now notice we multiply 3 by 210 to get 630
So it would make sense to multiply 5 by 210 to get 1050.
So we have 630:1050
Or in total 630 + 1050 = 1680 total books.
SHORTCUT:
Notice that since 3:5 is our lowest form we have 8 total books in this ratio.
We then notice again that we have multiplied by 210 to get to 630, but instead of finding the number of math books, we can just take 210 * 8 = 1680.