Q1 Andy had 50% more money than Ben. Ben had 20% more money than Dan. After Andy gave Ben and Dan a total of $360, and Ben gave Dan $400, the ratio of Andy's money to Ben's money to Dan's money became 1:1:2. How much money did Andy give to Ben.

Q2 4/5 of Charlie's present age is 1/3 of Ryan's age in 3 years' time. Their total age in 5 years' time is 58. What is Ryan's present age? Ans:33

Andy had 50% more money than Ben. Ben had 20% more money than Dan. After Andy gave Ben and Dan a total of $360, and Ben gave Dan $400, the ratio of Andy's money to Ben's money to Dan's money became 1:1:2. How much money did Andy give to Ben

For the first question, you can use Repeated Identity followed by Unchanged Total

4/5 of Charlie's present age is 1/3 of Ryan's age in 3 years' time. Their total age in 5 years' time is 58. What is Ryan's present age?

For this question, we can use a little bit of reasoning to get the total of Charlie present age and Ryan's age in 3 years to find the value of 1 unit.



Since 1unit is 12 years
Ryan's age is 3units less 3 years
--> 36 - 3 = 33 years

Hi Chris,
Thanks for your time, I still don't understand Q2. Any other method to solve?

Penny wrote:
Hi Chris,
Thanks for your time, I still don't understand Q2. Any other method to solve?
Hi Penny,
While waiting for Chris to reply, here's a non-model approrach which is slower than the Chris' models but still you will get full marks for getting the correct answer:

4/5 of Charlie's present age is 1/3 of Ryan's age in 3 years' time. Their total age in 5 years' time is 58. What is Ryan's present age?

Present ages
Charlie: 5u
Ryan: 48-5u

How to get Ryan's present age as 48-5u:

Total age in 5 years' time for Charlie and Ryan = 58
Total present age for Charlie and Ryan = 58-5-5=48
Since, present age for Charlie is 5u then present age for Ryan = 48-5u

3 years later
Age for Ryan = 48-5u+3=51-5u

4/5 of Charlie's present age is 1/3 of Ryan's age in 3 years' time.
4/5x(5u)=1/3x(51-5u)
4u=1/3x(51-5u)
51-5u=12u
17u=51
u=3

Ryan's present age = 48-5u = 48-5(3)=48-15 = 33 years old

Hi Perseverance,
Math is not easy for me. How to improve it? I hope I will not go crazy one day.