To make a bakery's signature chocolate muffins, a baker needs 2.5 ounces of chocolate for each muffin. how many pounds of chocolate are needed to make 48 signature chocolate muffins? (1(1left parenthesis, 1 pound = 16=16equals, 16 ounces))

we know that

to make 1 muffin-------------> needs 2.5 ounces of chocolate
  48 muffin-----------------------> X
X=48*2.5------> x=120 ounces of chocolate

if  1 pound-------------> 16 ounces
  X------------------> 120 ounces
x=120/16-----> x=7.5 pounds

the answer is
7.5 pounds