Hi I was wondering how much calling is if I am on the 40 cents per minute plan and planning to buy the $5 Canada/US calling add-on? Would the rate for 10 cents/min or would it would 50 (10+40) cents? Is the rate added upon my existing rate or is it solo?
Are you referring to the By the Minute 40¢ plan prepaid plan? As far as I am aware, that plan is no longer offered and those customers were migrated to the new $10.75 per month plan (see plans here). Which plan do you have?
Regardless, the per minute costs are for airtime only. Long-distance (LD) charges would be in addition to the airtime charges. So for your example, a LD call to the US with the $5 North American Long Distance Preferred Rate add-on would be 50¢ (40+10) per minute. A LD call to the US without the add-on would be 80¢ (40+40) per minute (see Full Details in link above).
Some plans include Canada-Wide calling. With those plans, the stated per minute costs include the LD charges within Canada. Your plan details should list whether your plan includes Canada-wide calling.
Hope this helps