Question 232379
OK
Let x=cost of dinner before tax and tip
Then 0.06x=sales tax
Cost of dinner after 6% sales tax would be (x+0.06x) or (1.06x)
The 15% tip would be 0.15(1.06x) or 0.159x
Then total cost would be:
x+0.06x+0.159x and this would equal $97.52.  So our equation to solve is:
x+0.06x+0.159x=$97.52  collect like terms
1.219x=$97.52  divide each side by 1.219

x=$80--------------------------cost of dinner before tax and tip

Hope this helps---ptaylor