If you solve this , you get me to do whatever you want

Hey guys!
I have an interesting puzzle for you all
If any person can solve this you can get me to do whatever you want on this site!!
the puzzle is:
A+B=15
B x C=84
C/4=3
B+D=18
SOLVE FORE D
(HINT: D is not 11)

@happymiss => D=18B

@saim23
that's the right answer
you can talk to me on chats and tell me whatever I have to do

@happymiss D is not 11

@happymiss are people really that dumb the answer is 11 just think about it

@RSharma hey dumb dumb ^^ tell me how atleast I tried to do some math, if I made a mistake fair enough but don't be like its 11 and laugh

@happymiss D is 6?

@whereTheGirlsAt
I'm sorry but D is not 6

A clue maybe? Can it be negative numbers too? And C/4 is 3?

@happymiss A=8,B=7,C=12 and D=11.All these values satisfies the equations.But i can't get that how D can't be 11

@happymiss
12 !?

12 if C is 14 and C/4 is 4

@happymiss how can i talk? Message me if you can.

@happymiss lol good luck! Thanks for wasting our time

@happymiss cant message you. I dont know why.

@saim23
go to my profile
click on the three dots
and click on start a chat

@happymiss a =8,b =7 c=12 d= 11

@RSharma
6+7 is not 18

@happymiss sorryyyyyyyy

@happymiss D=10 with full workings out ^_^
A+B=15
B x C=84
C/4=3
B+D=18
SOLVE FORE Dc/4=3
c=3x4
c=12
BxC=84
Bx12=84
b=84/12
84/12=7
B=7
A+B=15
A+7=15
A=157
A=8
B+D=18
8+D=18
D=188
D=10