Mike pays $2.79 for coffee every weekday morning on his way to work. On Saturdays, he goes to visit his mother and takes her out to her favorite coffee shop where he spends $7.83 for two coffees. How

Mike pays $2.79 for coffee every weekday morning on his way to work. On Saturdays, he goes to visit his mother and takes her out to her favorite coffee shop where he spends $7.83 for two coffees. How much does he spend per week for coffee?