Question 169468
{{{Cost+SalesTax=TotalCost}}}, working eqn
given ---->{{{system(Cost=Cost,Tax=0.87,TotalCost=16.86)}}}
Subst. Working eqn,
{{{Cost+0.87=16.86}}}
{{{Cost=16.86-0.87}}}
{{{highlight(Cost=15.99)}}}, Answer
Check the percentage of Tax:
Let {{{x=percent}}}
{{{Cost+(x)Cost=TotalCost}}}
{{{15.99+(x)15.99=16.86}}}
{{{15.99(1+x)=16.86}}} ---> {{{cross(15.99)(1+x)/cross(15.99)=16.86/15.99}}}
{{{(1+x)=1.0544}}}
{{{x=1.0544-1=0.0544*100}}}---------> x=5.44% (Tax)
.
Thank you,
Jojo