Get min and max value from subform

Get min and max value from subform

Hi, 
I would like to show the min and max values of the subform within the parent form e.g.

Parent Form = Products

Subform = Variations

Variation entry 1 - price =$200
Variation entry 2 - price =$300
Variation entry 3 - price =$400
Variation entry 4 - price =$500

The parent form would show "Price $200 to $500"


Please can someone advise on the deluge script I could use in the parent form to calculate this 

Many thanks