Question 316870
{{{(a+b+c+d)/4=(7(c+d)+c+d)/4}}}
{{{(a+b+c+d)/4=(7c+7d+c+d)/4}}}
{{{(a+b+c+d)/4=(8c+8d)/4}}}
{{{(a+b+c+d)/4=2c+2d}}}