Jamal has a drawer containing 6 green socks, 18 purple socks, and 12 orange socks. After adding more purple socks, Jamal noticed that there is now a 60% chance that a sock randomly selected from the drawer is purple. How many purple socks did Jamal add? A 6
B 9
C 12
D 18
E 24

18

Step-by-step explanation:

Trust me I did the amc 8

9

Step-by-step explanation:

18+12+6=30

30 total socks

after adding more purple socks (x) there are a total of 30+x socks and 18+x purple socks

(18+x)/(30+x)=6/10=3/5

using cross multiplication you get 5(18+x)=3(36+x) which is 90+5x=108+3x

this simplifies into 2x=18 therefore x=9

We can check this answer by putting it back in

18+9=27(purple socks)

36+9=45(total socks)

27/45=3/5=60%

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!