Numerical Ability
 What will be the maximum sum of 44, 42, 40, ........, 2, 0?

 502
 504
 506
 500
 502

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S_{n} = n [ 2a + (n  1)d ] 2
44, 42, 40,  2, 0
Here , a = 44 , d = 2 , n = 22 termsS_{22} = 22 [ 2 × 44 + (22  1)(2) ] 2 S_{22} = 22 [ 88  42 ] 2 S_{22} = 22 × [ 46 ] 2
S_{22} = 11 × 46 = 506Correct Option: C
S_{n} = n [ 2a + (n  1)d ] 2
44, 42, 40,  2, 0
Here , a = 44 , d = 2 , n = 22 termsS_{22} = 22 [ 2 × 44 + (22  1)(2) ] 2 S_{22} = 22 [ 88  42 ] 2 S_{22} = 22 × [ 46 ] 2
S_{22} = 11 × 46 = 506
 What will be the maximum sum of 44, 42, 40, ........, 2, 0?

 502
 504
 506
 500
 502

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S_{n} = n [ 2a + (n  1)d ] 2
44, 42, 40,  2, 0
Here , a = 44 , d = 2 , n = 22 termsS_{22} = 22 [ 2 × 44 + (22  1)(2) ] 2 S_{22} = 22 [ 88  42 ] 2 S_{22} = 22 × [ 46 ] 2
S_{22} = 11 × 46 = 506Correct Option: C
S_{n} = n [ 2a + (n  1)d ] 2
44, 42, 40,  2, 0
Here , a = 44 , d = 2 , n = 22 termsS_{22} = 22 [ 2 × 44 + (22  1)(2) ] 2 S_{22} = 22 [ 88  42 ] 2 S_{22} = 22 × [ 46 ] 2
S_{22} = 11 × 46 = 506
 Which of the following assertions are CORRECT?
P : Adding 7 to each entry in a list adds 7 to the mean of the list
Q : Adding 7 to each entry in a list adds 7 to the standard deviation of the list
R : Doubling each entry in a list doubles the mean of the list
S : Doubling each entry in a list leaves the standard deviation of the list unchanged

 P, Q
 Q, R
 P, R
 R, S
 P, Q

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P and R always holds true
Else consider a sample set {1, 2, 3, 4} and check accordingly.Correct Option: C
P and R always holds true
Else consider a sample set {1, 2, 3, 4} and check accordingly.
 An automobile plant contracted to buy shock absorbers from two suppliers X and Y. X supplies 60% and V supplies 40% of the shock absorbers. All shock absorbers are subjected to a quality test. The ones that pass the quality test are considered reliable. Of X's shock absorbers, 96% are reliable. Of Y's shock absorbers, 72% are reliable. The probability that a randomly chosen shock absorber, which is found to be reliable, is made by Y is

 0.288
 0.334
 0.667
 0.720
 0.288

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X Y Supply 60% 40% Reliable 96% 72% Overall 0.576 0.228 ∴ P(X) = 0.288 = 0.334 0.576 + 0.288
Correct Option: B
X Y Supply 60% 40% Reliable 96% 72% Overall 0.576 0.228 ∴ P(X) = 0.288 = 0.334 0.576 + 0.288
 A political party orders an arch for the entrance to the ground in which the annual conventions is being held. The profile of the arch follows the equation y = 2x – 0.1x^{2} where y is the height of the arch in meters. The maximum possible height of the arch is

 8 meters
 10 meters
 12 meters
 14 meters
 8 meters

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y = 2x – 0.1x^{2}
dy = 2 – 0.2x dx d^{2}y < 0 dx^{2}
Hence maximises at 2 – 0.2x = 0
⇒ x = 10
∴ y = 20 – 10 = 10 mCorrect Option: B
y = 2x – 0.1x^{2}
dy = 2 – 0.2x dx d^{2}y < 0 dx^{2}
Hence maximises at 2 – 0.2x = 0
⇒ x = 10
∴ y = 20 – 10 = 10 m