Abag of candy contains 300 pieces of which 28% are red.
how many pieces are not red

300 = Total candies
28% = Percent of candies that are red

100% - 28% = 72% 
72% = Percent of candies that are NOT red

My personal preference for setting up this type of question:

300 -> 100% (Total candies)
___ -> 72% (NOT red candies)
___ -> 28% (Red candies)

Next:

28% = 0.28
300 x 0.28 = 84
84 = Number of candies that are red

300 -> 100% (Total candies)
___ -> 72% (NOT red candies)
84   -> 28% (Red candies)

Now:

300 - 84 = 216

300 -> 100% (Total candies)
216 -> 72% (NOT red candies)
84 -> 28% (Red candies)

216 equals the number of candies that are NOT red.

What are the choices

Hello!

the answer is:

the answer is:

why?

to solve the problem, we need to remember the quotient of power property, it's defined by the following relation:

if we have a quotienf of powers that have the same base, we need to keep the same base and subtract the exponent of the denominator power to the exponent of the numerator power.

so, we are given the expression:

then, calculating we have:

hence, the answer is:

have a nice day!