ABC26GN0192 · Number System

Subject: General Aptitude · Chapter: Number System · Exam: · Marks: · Difficulty:

If $(64)^{2}-(36)^{2}=20 \times x$, then $x=$ ?
(a)70
(b)120
(c)180
(d)140
(e)None of these
Answer
Answer (as printed): D
Explanation
134. $$\begin{aligned} & (64)^{2}-(36)^{2}=20 \times x \Rightarrow(64+36)(64-36)=20 \times x \\ & \Rightarrow x=\frac{100 \times 28}{20}=140 . \end{aligned}$$

Explanation as extracted from the printed page; notation may be imperfect.

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