Simplification for IBPS PO test 4-Solved questions with detailed explanations for SSC, IBPS PO, SBI PO, RRB, RBI, CSE, CGL, CHSL, CDA, CSE, UPSC

16)

What will come in place of question mark (?) in the following questions

$\sqrt{360 - 225 \times 2 + 379} = ?$

[IBPS (PO), 2012]

A)
17
B)
19
C)
img
D)
289
E)
None of these

Answer: Option A

Explanation

$\begin{array}{l} Here, we follow VBODMAS rule, \\ So, \sqrt{360 - 450 + 379} \\ = \sqrt{360 + 379 - 450} \\ = \sqrt{739 - 450} \\ = \sqrt{289} = 17 \end{array}$

Hence, Option A is correct.

Discussion

17)

${(?)}^{2} \times {(12)}^{2} \div {(48)}^{2} = 81$

[PNB (PO), 2011]

A)
26
B)
32
C)
9
D)
15
E)
None of these

Answer: Option E

Explanation

$\begin{array}{l} {Here, (?)}^{2} \times {(12)}^{2} \div {(48)}^{2} = 81 \\ It can also be written as \\ {(?)}^{2} \times {(\frac{12}{48})}^{2} = 81 \Rightarrow {(?)}^{2} = 81 \times 16 \\ \Rightarrow ? = \sqrt{81 \times 16} \Rightarrow = 9 \times 4 = 36 \end{array}$

Hence, Option E is correct.

Discussion

18)

${(72)}^{2} {+ (61)}^{2} {= (199)}^{2} - {(?)}^{2} - 420$

[Bank of India (PO) , 2010]

A)
165
B)
198
C)
182
D)
171
E)
None of these

Answer: Option E

Explanation

$\begin{array}{l} Here, we can write it as \\ {= ?}^{2} {+ 420 = (199)}^{2} - { (72 )2 + (61)2} \\ {= ?}^{2} + 420 = 39601 - {5184 + 3721} \\ {= ?}^{2} + 420 = 39601 - {8905} \\ {= ?}^{2} + 420 = 30696 \\ = ? 2 = 30696 - 420 \\ = ? 2 = 30276 \\ ? = \sqrt{30246} = 174 \end{array}$

Hence, Option E is correct.

Discussion

19)

${[(144)}^{2} + 48 \times ?] \div 22 = 216$

[PNB (PO) , 2009]

A)
23
B)
16
C)
11
D)
32
E)
None of these

Answer: Option C

Explanation

$\begin{array}{l} {Here, [(144)}^{2} \div 48 \times ?] \div 22 = 216 \\ We follow the BODMAS rule. \\ \Rightarrow [\frac{144 \times 144}{48} \times ?] \div 22 = 216 \\ \Rightarrow (432 \times ?) \div 22 = 216 \\ \Rightarrow (432 \times ?) = 216 \times 22 \\ \Rightarrow ? = \frac{216 \times 22}{432} = 11 \end{array}$

Hence, Option C is correct.

Discussion

20)

$92 \times 576 \div 2 \sqrt{1296} {+ (?)}^{3} + \sqrt{49}$

[PNB (PO) , 2009]

A)
3
B)
img
C)
9
D)
27
E)
None of these

Answer: Option C

Explanation

$\begin{array}{l} Here, \\ 92 \times 576 \div 2 \sqrt{1296} + {(?)}^{3} + \sqrt{49} \\ We can also write it as \\ 92 \times 576 \div 2 \times {36 = (?)}^{3} + \sqrt{49} \\ \Rightarrow 92 \times 576 \div {72 = (?)}^{3} + \sqrt{49} \\ Here, we apply the BODMAS rule. \\ So, 92 \times {8 = (?)}^{3} + 7 \\ \Rightarrow 736 - {7 = (?)}^{3} \\ \Rightarrow (?) = {}^{3}{\sqrt{729}} = 9 \end{array}$

Hence, Option C is correct.

Discussion

Simplification-Test 4 (Based on Fractions/Square roots and Cube roots)

Answer: Option A

Answer: Option E

Answer: Option E

Answer: Option C

Answer: Option C