Step 1
Convert mixed number to an improper fraction
\(21\frac{1}{2}\ lb= \frac{21*2+1}{2} =\frac{43}{2}\ lb\)
Step 2
Find the total pounds used in tacos
we know that
Saeed used \(1/4\) of the beef to make tacos
so
\(\frac{1}{4}*\frac{43}{2}=\frac{43}{8}\ lb\)
Step 3
Find how many burgers did Saeed make
we know that
Saeed used \(2/3\) of the remainder to make quarter-pound burgers
Remember that
If Saeed used \(1/4\) of the beef to make tacos
then
the remainder is \(3/4\) of the beef
so
\(remainder=\frac{3}{4}*\frac{43}{2}=\frac{129}{8}\ lb\)
Multiply the remainder by \(2/3\)
\(\frac{2}{3}*\frac{129}{8}=\frac{129}{12}\ lb\)
Divide by \(1/4\) to find the number of burgers
\(\frac{(129/12)}{(1/4)} =\frac{129}{3}=43\ burgers\)
therefore
the answer is
\(43\ burgers\)
