Question 550201
let the bill amount be 				x										
Plan A			180	+	0.25	x								
Plan B=			250	+	0.20	x								
Plan B < Plan A														
250+0.25(x-250)<180+0.25(x-180	)
250+0.20x-62.5	<180+0.25x-45		
250-180	-62.5+45<0.25x-0.2x				
52.5	<	0.05	x 											
1050	<	x												
x should be greater than	$1050