Question
Find the value of \(\dfrac{1.4\times1.4\times1.4 - 1.2\times1.2\times1.2}{1.4\times1.4+1.4\times1.2+1.2\times1.2}\)
This question was previously asked in
RRB NTPC 2025 Graduate CBT 2 Question Paper PDF (10-Jul-2026) (Shift 1)
The correct answer is
0.2
Using the identity \(\dfrac{a^3-b^3}{a^2+ab+b^2} = a-b\), with a=1.4 and b=1.2.
Value: \(1.4-1.2 = 0.2\).
Hence, the value of the expression is 0.2.
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