Question 310472
Let {{{x}}} = number of homes with plan 1
Let {{{y}}} = number of homes with plan 2
Given:
{{{x + y = 56}}}
There are three times as many homes with plan 2 as with plan 1
This says {{{y/x = 3/1}}}
{{{y = 3x}}}
By substitution:
{{{x + 3x = 56}}}
{{{4x = 56}}}
{{{x = 14}}}
and, since {{{y = 3x}}}
{{{y = 3*14}}}
{{{y = 42}}}
There are 14 homes using plan 1
There are 42 homes using plan 2