Question 935763


Anders is {{{3}}} years younger than {{{Bo}}}. 

{{{Anders=Bo-3}}}..............(1)

Inga is three times as old as Anders. 

{{{Inga=3*Anders}}}............(2)

All three are together three times as old as Bo.

{{{Anders+Inga +Bo=3*Bo}}}............(3)



 How old is everyone?

{{{Anders+Inga +Bo=3*Bo}}}.............(3)substitute {{{Anders=Bo-3}}} and  {{{Inga=3*Anders=3(Bo-3)}}}

{{{(Bo-3)+3*(Bo-3) +Bo=3*Bo}}}

{{{Bo-3+3*Bo-9 +Bo=3*Bo}}}

{{{Bo-3+cross(3*Bo)-9 +Bo-cross(3*Bo)=0}}}

{{{2Bo-3-9 =0}}}

{{{2Bo-12 =0}}}

{{{2Bo =12}}}

{{{Bo =12/2}}}

{{{highlight(Bo =6)}}}


{{{Anders=Bo-3}}}..............(1)

{{{Anders=6-3}}}

{{{highlight(Anders=3)}}}


{{{Inga=3*Anders}}}

{{{Inga=3*3}}}

{{{highlight(Inga=9)}}}