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SSC Selection Post 2020 PYQ — Question 72

SSC Selection Post - Higher Secondary Level 2020 - 10 Nov 2020 - Shift 2 • Quantitative Aptitude • Q72

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If a + b + c = 6, a² + b²+c² = 30 and a3 + b³ + c3 = 165, then the value of 4abc is:

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Correct answer: C

Explanation

The correct answer is Option 3 i.e. 1.

a + b + c = 6,

a² + b²+c² = 30,

a3 + b³ + c3 = 165

ab + bc + ca = (36 − 30)/2 = 3
a³ + b³ + c³ = 216 − 18×3 + 3abc = 165
⇒ 3abc = 165 − 162 = 3 ⇒ abc = 1