Answer:
[tex]12 \div \frac{3}{4} = 12 \times \frac{4}{3} = 12 \times 4 \div 3 = 4 \times 4 = 16 \\ 16 \times 5 = 80 \: ft \: [/tex]
first you must know how many 3/4 do you have
because of scale
and after that multiply to 5 to get actual length
