A company that makes hair-care products had 4,000 people try a new shampoo. Of the 4,000 people,8 had a mild allergic reaction. What percent of the people had a mild allergic reaction?

b

step-by-step explanation:

a difference is the result of subtraction. while each of these expressions has subtraction in it, a difference will be the result when subtraction is the last operation applied in the order of operations for the expression. this means subtraction must be outside of the parenthesis. only b has this.

answer:

step-by-step explanation:

$6.42

step-by-step explanation:

cross multiplying, we get :

⇒ (3) × (5) = (9) × (x)

⇒ 15 = 9x