Question 88585
Let x=number of child tickets sold
Then x+30=number of adult tickets sold
And 3x=number of senior tickets sold

Now we are told that:

$1x+$12(x+30)+$4(3x)=$1110   get rid of parens ($ are understood)

x+12x+360+12x=1110  subtract 360 from both sides

x+12x+360-360+12x=1110-360  collect like terms

25x=750 divide both sides by 25

x=30------------------------number of child tickets sold

x+30=30+30=60----------------------------number of adult tickets sold

3x=3*30=90---------------------------------number of senior tickets sold

CK

30*1+60*12+90*4=1110

30+720+360=1110

1110=1110


Hope this helps---ptaylor