Adult tickets for a play cost $9 and child tickets cost $4. If there were 27 people at a performance and the theatre collected $143 from ticket sales, how many children attended the play?

Question

anonymous · Answer

11 children and 11 adults.
9x + 4x = 143
13x = 143
x=11

anonymous · Answer

Adult tickets for a play cost $9 and child tickets cost $4. If there were 27 people at a performance and the theatre collected $143 from ticket sales, how many children attended the play? 
 A. 19 children  
 
 B. 21 children  
 
 C. 20 children  
 
 D. 7 children

anonymous · Answer

oh ok

anonymous · Answer

its D

whpalmer4 · Answer

a = # of adults
c = # of children
a+c = 27
9a + 4c = 143

Solve by substitution or elimination

anonymous · Answer

Thank you walidfarhat it's confusing to me the way it is worded.

luigi0210 · Answer

It'd be easier to substitute

anonymous · Answer

listen to luigi

anonymous · Answer

what i did was try everything
its D
7x4=28+9(15)= 143

luigi0210 · Answer

so either set the top equal to a or c, and plug it into the other equation

whpalmer4 · Answer

Elimination is easy, too:
multiply first eqn by -4:
$$-4a -4c = -108$$$$9a+4c = 143$$
---------------
$5a=35$
etc.

whpalmer4 · Answer

It's not D.  D is 7 children and 27-7 = 20 adults.  Adults pay $9 each, so right there that's $180, which is > the $143 collected. 

Always, always check your result to make sure it actually solves the problem when doing word problems (or any problems, really).

anonymous · Answer

Thank you all for your help