Not too sure about the above answer...

In any event. Breakeven is equal to: Fixed Costs/Selling Price less your variable costs.

In this scenario fixed costs are the $800 per month. Selling price is the $60 (which is not the variable cost per your question) rather the $20 would be considered the variable cost. Bear in mind if it were the adverse there would never be a breakeven as it could theoretically not happen.

So, 800/60-20 or 800/40 or 20 lessons.

To check; 20 lessons at 60 equals 1,200

20 lessons at 20 equals (400) * this is in brackets indicating a negative integer as this is the VC.

=800

(800) * Fixed costs

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