



 
Hi Bev, A little bit of algebra will get you what you need. Suppose the total revenues before any taxes is $\$T.$ To calculate the total sales after taxes you need to do two things.
Thus the total revenue including taxes is $\$T + 0.05 \times \$T + 0.056 \times \$T = 1.106 \times \$T.$ But you know this is $\$116 391.38$ so \[1.106 \times \$T = \$116 391.38\] Dividing both sides by 1.106 yields \[\$T = \frac{\$116 391.38}{1.106} = \$105 236.33\] Finally, what is the PST? It is $7\%$ of $80\%$ of $\$T.$ Penny  


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