In order to calculate a loan to value, you take the appraised value and then take a % to calculate the total loan to value.
For example if you appraise a home at 100,000 and your down payment is 10% or 10000 then your loan to value is 90%
Hencd by that logic if you add 100000 more to the calculation then you can prove that 20% of 200000 is 20,000 hence the loan to value would be 180,000/200,000 which gives you a 90% value
