Radio button bill

Select the call or sms radio button. Update the appropriate total and the global total when the ADD button in pressed.

Calls costs R2.75 and a SMS R0.75
If the total cost exceed R30.00 show the total cost in orange, if over R50 show it in red.

What is the benefit of using radio buttons?
Bill type
Totals
Call total R34.50
SMS total R3.00
Total R37.50