Question

lisa uses 3 pounds of sugar to make 100 cookies. How many cookies can she make with 5 pounds of sugar. round to the nearest whole cookie

Answer 1

\(\large \begin{array}{llll}
sugar&cookies\\
3&100\\
5&x
\end{array}\implies \cfrac{3}{5}=\cfrac{100}{x}\)

Answer 2

set up a proportion

3/100 = 5/x (3 lbs sugar to 100 cookies = 5 lbs to x cookies)
cross multiply
(3)(x) = (100)(5)
3x = 500
x = 500/3
x = 166.66 = 167 cookies