Question 133323
Given: 70 homes sold.  Let the number of homes Fred sells be f. Then the number Marika sold is 2.5f

{{{70 = freddie sales + Marika sales}}}
{{{ 70 = f + 2.5f }}}
{{{ 70 = 3.5f}}}
20 = f
Freddie sold 20.
Marika = 2.5 * 20 = 50