SOLUTION: The ages of two brothers are in the ratio two to three, but in eight years, the ratio of their ages will be three to four. What is the age of the older brother?

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: The ages of two brothers are in the ratio two to three, but in eight years, the ratio of their ages will be three to four. What is the age of the older brother?      Log On


   



Question 435314: The ages of two brothers are in the ratio two to three, but in eight years, the ratio of their ages will be three to four. What is the age of the older brother?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The ages of two brothers are in the ratio two to three, but in eight years, the ratio of their ages will be three to four. What is the age of the older brother?
---
Let the brothers be a and b.
Equations:
a/b = 2/3
(a+8)/(b+8) = 3/4
----------------------------
Cross multiply:
3a = 2b
4(a+8) = 3(b+8)
-----
a = (2/3)b
4a+32 = 3b+24
---
substitute for "a" and solve for "b":
4(2/3)b + 32 = 3b+24
[(8/3)-(9/3)]b = -8
(-1/3]b = -8
b = 24 years old
----
a = (2/3)b
a = (2/3)24
a = 16 years old
===========================
Cheers,
Stan H.
===========