If a deli sells a sandwich spread for 6.40 per pound. how much do you have to pay for 24 ounces of the spread?

You have to pay $9.60 for 24 ounces of the sandwich spread.

Given:
Unit cost of sandwich spread = $6.40 per pound
Weight of sandwich spread = 24 ounces

We need to convert the ounces into pound before we can compute the cost of the sandwich spread.

1 pound is equivalent to 16 ounces.

24 ounces x 1 pound/16 ounces = 24 pound/16 = 1.5 pounds

total cost of 24 ounces sandwich spread 

1.5 pounds x $6.40 per pound = $9.60