(.125 + .027) / (.5 x .5 - 1.5 + .09) =?

Given expression
= [(0.5)³ + (0.3)³] / [(0.5)² - 0.5 x 0.3 + (0.3)²]
= [a³ + b³] / [a² - ab + b²]
= [(a + b)(a² - ab + b²)] / [a² -ab + b²]
= a+b
= 0.5 + 0.3
= 0.8