Question

72 is what precent of 400? Write and solve an equaion to solve the problem

Answer 1

18%

Answer 2

Use the names of operations to convert this to an algebraic equation:
"is" means "="
Percent means "/100" (divided by 100)
"of" means "*" (multiply)
"what number" means to insert your favorite letter for a variable (usually the letter x)
72=18/100 * x
72 = .18x
72/.18 = x
400 = x
Mental Check: 10% of 400 is 1/10 of 400 which is 40.
20% of 400 is 2/10 of 400 which is 80.
Is 72 larger than 40, less than 80 but closer to 80? Yes. So I think we're at least close.
Use your calculator: 18% of 400 or .18 * 400 = 72!!