A 39-foot flagpole has a 21-foot shadow. If a man standing next to the flagpole has a 3.5-foot shadow, how tall is the man?

He's 6.5 feet tall.  

Step-by-step explanation:

Set up ratios 3.5/21 = x/39 and use the butterfly method.

distance covered by pamela in 9 l of fuel = 99km

let us apply unitary method here.

distance covered by pamela in 1 l of fuel =99/9 =11 km

now let us find distance covered by pamela if she has 12 l of fuel.

distance covered in 12 l = distance covered in 1 l of fuel * 12

we know that distance covered by here in 1 l is 11 km.

so distance covered in 12 l of fuel = 11*12 = 132 km.