71. A number of boys raised Rs. 12,544 for a famine fund, each boy has given as many rupees as there were boys. The number of boys was :

1. 1. 102

   
   
   

   2. 112

   
   
   

   3. 122

   
   
   

   4. 132

   
   
   

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1. View Hint View Answer Discuss in Forum

   Number of boys = √12544 = 112
   Illustration :
   

   Correct Option: B

   Number of boys = √12544 = 112
   Illustration :
   

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72. If 5416 * 6 is a perfect square, then the digit at ‘*’ is :

1. 1. 9

   
   
   

   2. 4

   
   
   

   3. 6

   
   
   

   4. 5

   
   
   

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1. View Hint View Answer Discuss in Forum

   
   ∵  1466 × 6 = 8796
   ∴  * = 9

   Correct Option: A

   
   ∵  1466 × 6 = 8796
   ∴  * = 9

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73. The least number that should be subtracted from the number 32146 to make it a perfect square is :

1. 1. 305

   
   
   

   2. 105

   
   
   

   3. 205

   
   
   

   4. 405

   
   
   

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1. View Hint View Answer Discuss in Forum

   √32146 > 179
   179 × 179 = 32041
   ∴  Required answer
   = 32146 – 32041 = 105

   Correct Option: B

   √32146 > 179
   179 × 179 = 32041
   ∴  Required answer
   = 32146 – 32041 = 105

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74. The sum of the perfect squares between 120 and 300 is

1. 1. 1400

   
   
   

   2. 1296

   
   
   

   3. 1024

   
   
   

   4. 1204

   
   
   

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1. View Hint View Answer Discuss in Forum

   Required sum = 121 + 144 + 169 + 196 + 225 + 256 + 289 = 1400

   Correct Option: A

   Required sum = 121 + 144 + 169 + 196 + 225 + 256 + 289 = 1400

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75. The least number that must be subtracted from 63520 to make the result a perfect square is :

1. 1. 16

   
   
   

   2. 20

   
   
   

   3. 24

   
   
   

   4. 30

   
   
   

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1. View Hint View Answer Discuss in Forum

   Obviously, 16 must be subtracted to make the result a perfect square.
   i.e.  63520–16 = √63504 = 252

   Correct Option: A

   Obviously, 16 must be subtracted to make the result a perfect square.
   i.e.  63520–16 = √63504 = 252

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