The ratio of two numbers is 3:5. When 4 is subtracted from the lesser of the two numbers and 8 is added to the larger of the two, the new ratio is 2:7. What is the greater of the two numbers before 8 is added to it?
I decided to make the smaller number x and the larger number y. Here is what I have, x:y = 3:5 and x-4:y+8=2:7.
I do not know what to do after this. CAn someone help explain? I do not want answers.
+128406 Let the smaller number = x and the greater = y
We know that
x / y = 3/5 ⇒ x = (3/5)y (1)
And we know that
[ x - 4] 2
______ = ___
[y + 8] 7
Sub (1) into this for x
[ (3/5)y - 4 ] 2
_________ = ___
[ y + 8] 7
Cross-multiply and you have
7 [ (3/5)y - 4 ] = 2 [ y + 8]
You should be able to solve it now for the larger number, y
