Selling Price = Cost + Markup
The Markup is an additional 60% of the cost, so:
Selling Price = Cost + 0.60*Cost [Express 60% as a decimal 0.60]
Selling Price = Cost*(1 + 0.60)
Selling Price = Cost*(1.6)
(Selling Price)/(1.6) = Cost
Selling Price is $14. Can you finish it from here?