Question 1151038
A family's vacation destination is {{{850}}} miles from their home. 
{{{d=800mil}}}

They travel by car {{{t[1]=6h}}}on the first day of their trip. Their average speed is {{{s[1]=45(mil/h)}}}

{{{d[1]=s[1]*t[1]}}}
{{{d[1]=45(mil/h)*6h}}}
{{{d[1]=45(mil/cross(h))*6cross(h)}}}
{{{d[1]=45mil*6}}}
{{{d[1]=270mil}}}->the first day of their trip

 The next day they travel {{{t[2]=7h}}}, averaging the {{{same}}} speed. 

{{{d[2]=s[2]*t[2]}}}
{{{d[2]=45(mil/h)*7h}}}
{{{d[2]=45(mil/cross(h))*7cross(h)}}}
{{{d[2]=45mil*7}}}
{{{d[2]=315mil}}}->the second day of their trip

How many miles are left for the family to travel?

 in two days they have  traveled: {{{d[1]+d[2]=270mil+315mil=585mil}}}

{{{d-(d[1]+d[2])=800mil-585mil=215mil}}}

answer: {{{215mil}}} are left for the family to travel