(0.9 * 0.9 – 0.8 * 0.8)/1.7 = ________?

A. 0.1
B. 0.2
C. 0.3
D. 0.4

Explanation:

As numerator is of the form a2 – b2 = (a + b) (a – b), so the given expression simplifying becomes

(0.92 – 0.82)/(0.9 + 0.8) (0.9 + 0.8) (0.9 – 0.8)/0.9 + 0.8 = 0.1