Question 318654
{{{(1/2)(x+(x+10)+(x+20))=90}}}
{{{(x+(x+10)+(x+20))=180}}}
{{{(3x+30)=180}}}
{{{3x=150}}}
{{{x=50}}}
50,60,70
<p>
50+60+70=180/2=90
multiples of 10 are 10, 20, 30, 40, 50, 60, 70, 80, 90, 100....