The amount he should put in the college savings account 

Solution:
Given, income of Mark = 

Percentage of amount in college savings account = 

To find: The amount he should put in the college savings account
This can be solved in two methods as follows:
Method 1:
As given, Mark puts 
 of the total amount in the account
 of the total amount in the account
i.e. 

On solving,

Method 2:
So, here assume that 100 corresponds to 2200 
As given, Mark puts 
 of the total amount in the account
 of the total amount in the account


Hence, the amount is 
