Number System
-  The simplified value of 1 − 1   1 − 1   1 − 1  ........  1 − 1   1 − 1  3 4 5 99 100 
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                        View Hint View Answer Discuss in Forum 2 × 3 × 4 ×......× 98 × 98 3 4 5 99 100 = 2 = 1 100 50 Correct Option: C2 × 3 × 4 ×......× 98 × 98 3 4 5 99 100 = 2 = 1 100 50 
-  The sum of the squares of two positive numbers is 100 and difference of their squares is 28. Find the sum of the numbers :
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                        View Hint View Answer Discuss in Forum According to question 
 x2 + y2 = 100 ...(i)
 x2 − y2 = 28 ...(ii)
 Adding both the equations
 x2 + y2
 x2 − y2
 -----------
 2x2 128
 ⇒ x2 = 64 ∴ x = 8
 From the equation (i)
 y2 = 100 − 64 ∴ y = 6
 So, x + y = 8 + 6 = 14Correct Option: CAccording to question 
 x2 + y2 = 100 ...(i)
 x2 − y2 = 28 ...(ii)
 Adding both the equations
 x2 + y2
 x2 − y2
 -----------
 2x2 128
 ⇒ x2 = 64 ∴ x = 8
 From the equation (i)
 y2 = 100 − 64 ∴ y = 6
 So, x + y = 8 + 6 = 14
-  The numbers 1, 3, 5,7 .., 99 and128 are multiplied together. The number of zeros at the end of the product must be :
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                        View Hint View Answer Discuss in Forum In 2m × 5n, the number of zeros 
 = n when m ≥ n
 = m when m < n
 Here, 128 = 27
 In 1 × 3 × 5 × 7 × ... × 99 multiples of 5 are 5, 15, 25, 35, 45, 55, 65, 75, 85, 95 (= 510)
 Clearly, 7 zeros will be found in the product.Correct Option: CIn 2m × 5n, the number of zeros 
 = n when m ≥ n
 = m when m < n
 Here, 128 = 27
 In 1 × 3 × 5 × 7 × ... × 99 multiples of 5 are 5, 15, 25, 35, 45, 55, 65, 75, 85, 95 (= 510)
 Clearly, 7 zeros will be found in the product.
 
	