The amount deposited in the account that earns 3.6% interest is $57,600 and the amount  deposited in the account that earns 2.1% interest is $192,400
The first step is to determine the amount of interest he earned in total over a year
Interest = Amount in the account - amount deposited 
$256,114 -  $250,000 = $6,114
The second step is to formulate two set of equations and use simultaneous equation to solve the question
a + b = $250,000 equation 1
0.036a + 0.021b = $6,114 equation 2 
Where a represent amount deposited in the account that earns 3.6% interest 
b  represent amount deposited in the account that earns 2,1% interest 
Multiply equation 1 by 0.036 
0.036a + 0.036b = 9000 equation 3 
Subtract equation 2 from 3
2886 = 0.015b
divide both sides of the equation by 0.015 
b = $192,400
Substitute for b in equation 1
a + 192,400 = 250,000 
a = 250,000 - 192400 
a = $57,600
To learn more about simultaneous equations, please check: brainly.com/question/23589883?referrer=searchResults