Find the value of \( \large\frac{1.2 \times 1.2 \times 1.2 - 0.2 \times 0.2 \times 0.2 }{1.2 \times 1.2 + 1.2 \times 0.2 + 0.2 \times 0.2 } \)


A) 1.2

B) 1

C) 0.2

D) 1.4

Correct Answer:
B) 1

Description for Correct answer:

Given sum is based on the following formula

\( a^{3} - b^{3} = (a - b)(a^{2}+ab+b^{2}) \)

\( \large\frac{a^{3}-b^{3}}{a^{2}+ab+b^{2}} = a - b \)

= \( \large\frac{1.2 \times 1.2 \times 1.2 – 0.2 \times 0.2 \times 0.2}{1.2 \times 1.2 + 1.2 \times 0.2 + 0.2 \times 0.2} \)

a = 1.2; b = 0.2

a – b = 1.2 – 0.2

a – b = 1


Part of solved TNPSC Question Paper-2015 questions and answers : Exams >> TNPSC >> TNPSC Question Paper-2015








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