This box plot represents the marks gained by students in an exam. Nobody gained exactly 30, 48 or 70 marks. 120 students gained less than 70 marks. How many students gained more than 48 marks?

hello from mrbilldoesmath!

answer:

25x^2 + 90x + 84

discussion:

mn(x) = m(n(x)) = m( 5x + 9) =

(5x + 9)^2 + 3 =>

25x^2 + 90x + 9^2 + 3 =

25x^2 + 90x + 84                 (as 9^2 = 9*9 = 81)

which is the second choice

regards,  

mrb

p.s.   i'll be on vacation from friday, dec 22 to jan 2, 2019. have a great new year!

2

step-by-step explanation:

x= cost per bracelet

number of bracelets * x + shipping charge = total cost

so

9x+9=72