Word Problem help please - Age

[newbie01.others]

Hi,

Am trying to help my autistic boy and unfortunately am not very good with math. He has a Age Word Problem as below:

Bill and Ben are brothers the sum of their ages is equal to 4 times Bob's age who is half as old as Bridget. The average age of the 4 children is 8. Write this as an equation, then solve it.

I tried to work out the equations and came out with something as below:

A=Bill's age
B=Ben's age
C=Bob's age
D=Bridget's age

A + B = 4C
D = 2C
A + B + C + D = 32

When I tried to work out the values, am not coming up with a whole number as the answer. Also am getting an invalid age value for A and B as well. What am I doing wrong?

Any advice will be much appreciated. Thanks in advance.

[maggiemagnet]

Bill and Ben are brothers the sum of their ages is equal to 4 times Bob's age who is half as old as Bridget. The average age of the 4 children is 8. Write this as an equation, then solve it.

Try starting with "translating" like they explain here and then looking at this "age problems" lesson and how to solve the equation. Since they define Bob in terms of Bridget and then define Bill and Ben in terms of Bob, start with Bridget:

Bridget's age: b

Then Bob is b/2. Bill and Ben can be "L" and "N" -- from the last letters of their names -- and then L + N = 4(b/2) = 2b. The average is the total divided by 4. See what this gives you. (P.S.: I don't think you can find Bill's and Ben's ages; you can only find Bridget's and Bob's. You don't have enough information to find the other two.)