title: Set opportunity amount filed value as default value in related object field
body: <p>I have a custom object <strong>FlightRequest</strong> for <strong>Opportunity</strong> object and there is an <strong>Amount</strong> filed both in <strong>opportunity</strong> and <strong>FlightRequest</strong>.</p>
  
  <p>I want to set <strong>Opportunity</strong>'s <strong>Amount</strong> filed value as default in <strong>FlightRequest</strong>'s <strong>Amount</strong> Field. So whenever <strong>New Button</strong> clicked for <strong>FlightRequest</strong>, <strong>Amount</strong> input should already field with <strong>Opportunity</strong>'s <strong>Amount</strong></p>
  
  <p>I m using <strong>Standard page layout</strong> not any visual force page layout and can not use it.</p>
  
  <p>I saw there is an option to set default value for a field but Opportunity object is not shown in <strong>Select Field Type</strong> options</p>
  
  <p>please advice how can i accomplish this</p>
  
  <p>thanks in advance</p>