341. The value of 25 – 5 [2 + 3 (2 – 2 (5 – 3) + 5) – 10] ÷ 4 is :

1. 1. 5

   
   
   

   2. 23.25

   
   
   

   3. 23.75

   
   
   

   4. 25

   
   
   

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1. View Hint View Answer Discuss in Forum

   Expression
   = 25 – 5 [2 + 3 {2 – 2(5 – 3) + 5} – 10] ÷ 4
   = 25 – 5 [2 + 3 {2 – 2 × 2 + 5} – 10] ÷ 4
   = 25 – 5 [2 + 9 – 10] ÷ 4
   

   = 25 − 5 ÷ 4 = 25 −	5
   	4

   
   

   =	100 − 5	=	95	= 23. 75
   	4		4

   Correct Option: C

   Expression
   = 25 – 5 [2 + 3 {2 – 2(5 – 3) + 5} – 10] ÷ 4
   = 25 – 5 [2 + 3 {2 – 2 × 2 + 5} – 10] ÷ 4
   = 25 – 5 [2 + 9 – 10] ÷ 4
   

   = 25 − 5 ÷ 4 = 25 −	5
   	4

   
   

   =	100 − 5	=	95	= 23. 75
   	4		4

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342. Find the sum of the following :

     1	+	1	+	1	+	1	+	1	+	1	+	1	+	1
     9		6		12		20		30		42		56		72

1. 1. 1

      2

   
   
   

   2. 0

   
   
   

   3. 1

      9

   
   
   

   4. 1

      2520

   
   
   

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1. View Hint View Answer Discuss in Forum

   =	1	+	1	+	1	+	1	+	1	+	1	+	1	+	1
   	9		6		12		20		30		42		56		72

   
   

   =	1	+	1	+	1	+	1	+	1	+ .....	1
   	9		2 × 3		3 × 4		4 × 5		5 × 6		8 × 9

   
   

   =	1	+	1	−	1	+	1	−	1	+ ... +	1	−	1	=	1
   	9		2		3		3		4		8		9		2

   
   
   Second Method :
   

   1	+	1	+	1	+	1	+	1	+	1	+	1	+	1
   9		6		12		20		30		42		56		72

   
   

   =

   1

   +

   1

   +

   1

   +

   1

   +

   1

   +

   1

   +

   1

   +

   1

   9

   2 × 3

   3 × 4

   4 × 5

   5 × 6

   6 × 7

   7 × 8

   8 × 9

   
   

   =	1	+		1	−	1
   	9			2		(2 + 7)

   
   ∵  n = 2 and r = 7
   

   =	1	+	1	−	1	=	1
   	9		2		9		2

   Correct Option: A

   =	1	+	1	+	1	+	1	+	1	+	1	+	1	+	1
   	9		6		12		20		30		42		56		72

   
   

   =	1	+	1	+	1	+	1	+	1	+ .....	1
   	9		2 × 3		3 × 4		4 × 5		5 × 6		8 × 9

   
   

   =	1	+	1	−	1	+	1	−	1	+ ... +	1	−	1	=	1
   	9		2		3		3		4		8		9		2

   
   
   Second Method :
   

   1	+	1	+	1	+	1	+	1	+	1	+	1	+	1
   9		6		12		20		30		42		56		72

   
   

   =

   1

   +

   1

   +

   1

   +

   1

   +

   1

   +

   1

   +

   1

   +

   1

   9

   2 × 3

   3 × 4

   4 × 5

   5 × 6

   6 × 7

   7 × 8

   8 × 9

   
   

   =	1	+		1	−	1
   	9			2		(2 + 7)

   
   ∵  n = 2 and r = 7
   

   =	1	+	1	−	1	=	1
   	9		2		9		2

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343. The value of
     

1. 1. 2

   
   
   

   2. 1

   
   
   

   3. 1

      2

   
   
   

   4. 2

      3

   
   
   

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1. View Hint View Answer Discuss in Forum

   (2/3) ×			3
   	5	÷	2	of 1	1
   	6		3		4

   = (2/3) ×			3
   	5	÷	2	of	5
   	6		3		4

   
   

   = (2/3) ×		3
   	5	÷	10
   	6		12

   
   

   = (2/3) ×		3
   	5	×	12
   	6		10

   
   

   =	2	×	3	= 2
   	3		1

   Correct Option: A

   (2/3) ×			3
   	5	÷	2	of 1	1
   	6		3		4

   = (2/3) ×			3
   	5	÷	2	of	5
   	6		3		4

   
   

   = (2/3) ×		3
   	5	÷	10
   	6		12

   
   

   = (2/3) ×		3
   	5	×	12
   	6		10

   
   

   =	2	×	3	= 2
   	3		1

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344. The value of 0.008 × 0.01 × 0.072 ÷ (0.12 × 0.0004) is :

1. 1. 1.2

   
   
   

   2. 0.12

   
   
   

   3. 0.012

   
   
   

   4. 1.02

   
   
   

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1. View Hint View Answer Discuss in Forum

   Using Rule 1,
   0.008 × 0.01 × 0.072 ÷ (0.12 × 0.0004)
   = 0.008 × 0.01 × 0.072 ÷ (0.000048)
   

   = 0.008 × 0.01 ×	0.072
   	0.000048

   
   

   =	0.00000576	= 0.12
   	0. 000048

   Correct Option: B

   Using Rule 1,
   0.008 × 0.01 × 0.072 ÷ (0.12 × 0.0004)
   = 0.008 × 0.01 × 0.072 ÷ (0.000048)
   

   = 0.008 × 0.01 ×	0.072
   	0.000048

   
   

   =	0.00000576	= 0.12
   	0. 000048

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345. If 50/* =	*
     	12	1
     		2

     then the value of * is :

1. 1. 25

      2

   
   
   

   2. 4

      25

   
   
   

   3. 4

   
   
   

   4. 25

   
   
   

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1. View Hint View Answer Discuss in Forum

   Let the value of * be x.
   

   ∴  (50/x) =	x
   	12	1
   		2

   
   

   ⇒	50	=	2x
   	x		25

   
   ⇒  2x² = 50 × 25
   ⇒  x² = 25 × 25
   ∴  x = 25

   Correct Option: D

   Let the value of * be x.
   

   ∴  (50/x) =	x
   	12	1
   		2

   
   

   ⇒	50	=	2x
   	x		25

   
   ⇒  2x² = 50 × 25
   ⇒  x² = 25 × 25
   ∴  x = 25

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