Lesson 4: Remix Fund Me: Why can't we divide (ethPrice * ethAmount) by 1e36 instead of 1e18?

[SimasG]

In the Remix Fund Me lesson, we're setting a minimum USD value ($50) required for the transaction to come through.

When calculating the ETH amount in USD, we leave 18 decimals in the returned answer.
uint256 ethAmountInUsd = (ethPrice * ethAmount) / 1e18;

However, then it is also necessary to adjust the minimumUsd value by multiplying it by 1e18.
uint256 public minimumUsd = 50 * 1e18;

Wouldn't it be easier/more readable to divide (ethPrice * ethAmount) by 1e36 instead of 1e18 so we wouldn't need to adjust the minimumUsd value?
I.e.
uint256 ethAmountInUsd = (ethPrice * ethAmount) / 1e36;
uint256 public minimumUsd = 50;

I may be missing something important and would appreciate your input. Cheers!

[PatrickAlphaC]

You could do that too :)

i just like having everything with 18 decimals so I always know what I'm working with!