Saeed bought 21 and 1/2 lb. of ground beef. He used 1/4 of the beef to make tacos and 2/3 of the remainder to make a quarter pound burgers. How many burgers did he make?

This may be a little complicated, but basically you have to break everything down into decimals. 21.5 X. 25 = 5.375. Subtract 5.375 from 21.5 and you should get 10.75 or 10 3/4. Divide 10 3/4 by 1/4, the answer should be 30 burgers.