Question 802659
{{{x}}}= number of phones
{{{y}}}= number of tabs
We use the information given to set a system of linear equations to find {{{x}}} and {{{y}}}.
{{{x+y=310}}}
After 1/3 of the phones were sold, there are {{{x-(1/3)x=(2/3)x}}} left.
After 10/11 of the tabs were sold, there are {{{y-(10/11)y=(1/11)y}}} left.
Since {{{(2/3)x}}} is thrice as many as {{{(1/11)y}}},
{{{(2/3)x=3*(1/11)y}}}
{{{(2/3)x=(3/11)y}}}
{{{33*(2/3)x=33*(3/11)y}}}
{{{22x=9y}}}
{{{y=(22/9)x}}}
So {{{x+(22/9)x=310}}}-->{{{(31/9)x=310}}}-->{{{x=310*9/31}}}-->{{{x=90}}}
So {{{y=(22/9)90}}}-->{{{y=220}}}
 
{{{t}}}= price of a tab, in $
so {{{t+714}}}= price of a phone, in $
{{{90(t+714)}}}= how much all the phones originally in the shop cost
${{{220t+2484)}}}= $2484 more than what all the tabs originally in the shop cost
{{{220t+2484=90(t+714)}}}
{{{220t+2484=90t+64260}}}
{{{220t-90t=64260-2484}}}
{{{130t=31776}}}
{{{t=31776/130}}} --> {{{highlight(t=475.2)}}}