NIELIT 2022 Feb Scientist D - Section A: 14

Question

Find out the missing number :

$$\begin{array}{|c|c|c|} \hline 2 & 3 & 5 \\\hline 9 & 17 & 33 \\\hline 65 & 129 & ? \\\hline \end{array}$$

• A. $228$
• B. $199$
• C. $257$
• D. $209$

Answer 1

for the given number patterns are:

• $2\times 2-1=3$
• $3\times 2-1=5$
• $5\times 2-1=9$
• $9\times 2-1=17$
• $17\times 2-1=33$
• $33\times 2-1=65$
• $65\times 2-1=129$
• $129\times 2-1=257$

So the missing number is $257$, Option (C) is correct.