Can you explain how to solve this math problem: Vaishali wears a beautiful piece of clothing called a Saree,  a traditional Indian dress for women.  It is mostly tangerine-colored, with blue, brown, and gold-colored decorative stripes.  There are three times as many gold stripes as brown stripes, and five times as many blue stripes as gold stripes. If there are 4 brown stripes, how many blue stripes does Vaishali's Saree have?