Renting a car cost 30dollars a day, or 600 per month. Renting daily is cheaper for a few days, but after how many days are the two options equal. (After which renting is cheaper)

The two options are equal after 20days of daily pay.

Step-by-step explanation:

If it cost $30 to rent a car for a day and $600 to rent the same car for a month(approximately 30days), renting daily is equal to the monthly rentage after 20 days ($30 for 20days which is $30×20 i.e $600)

According to the deduction above, the renting is cheaper daily only for the first 20 days after which the amount equals to the monthly rentage of the same car.