Simplify the expression:
(0.2)3 + (0.3)3 + (0.5)3 + 3 × 0.5 × 0.7 × 0.8
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. 1.000.
If a + b + c = 1 then a3 + b3 + c3 + 3abc = (a + b + c)3
Here, 0.2 + 0.3 + 0.5 = 1
So, (0.2)3 + (0.3)3 + (0.5)3 + 3 × 0.5 × 0.7 × 0.8 = (0.2 + 0.3 + 0.5)3 = 1.000