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- Question
A Cricket team of 23 people all shake hands with each other exactly once. How many hand shakes occur ?
Options- A. 142
- B. 175
- C. 212
- D. 253
- Correct Answer
- 253
ExplanationThe first person shakes hands with 22 different people, the second person also shakes hands with 22 different people, but one of those handshakes was counted in the 22 for the first person, so the second person actually shakes hands with 21 new people. The third person, 20 people, and so on...
So,
22 + 21 + 20 + 19 + 18 + 17 + 16 + 15 + 14 + 13 + 12 + 11 + 10 + 9 + 8 + 7 + 6 + 5 + 4 + 3 + 2 + 1
= n(n+1)/2 = 22 x 23 /2 = 11 x 23 = 253. - 1. At what time between 5 and 6 o' clock are the hands of a 3 minutes apart ?
Options- A. 24min
- B. 12min
- C. 13min
- D. 14min Discuss
- 2. A line cuts two concentric circles. The lengths of chords formed by that line on the two circles are 4 cm and 16 cm. What is the difference (in cm2) in squares of radii of two circles?
Options- A. 240
- B. 120
- C. 60
- D. 90 Discuss
- 3. On dividing 4150 by a certain number , the quotient is 55 and the remainder is 25, the divisor is
Options- A. 68
- B. 65
- C. 70
- D. 75 Discuss
- 4. At what time between 2 and 3 o'clock will the hands of a clock be together?
Options- A. (9 + 10/11) min past 2
- B. (10 + 10/11) min past 2
- C. (11 + 10/11) min past 2
- D. (12 + 10/11) min past 2 Discuss
- 5. The difference between a positive proper fraction and its reciprocal is 9 / 20. Then the fraction is :
Options- A. 3/5
- B. 3/10
- C. 4/5
- D. 5/4 Discuss
- 6. What is the greatest of 3 consecutive integers whose sum is 24 ?
Options- A. 6
- B. 7
- C. 8
- D. 9 Discuss
- 7. At what angle the hands of a clock are inclined at 15 minutes past 5?
Options- A. 57.5 degrees
- B. 67.5 degrees
- C. 77.5 degrees
- D. 87.5 degrees Discuss
- 8. A watch which gains 5 seconds in 3 minutes was set right at 7 a.m. In the afternoon of the same day, when the watch indicated quarter past 4 o'clock, the true time is:
Options- A. 4pm
- B. 5pm
- C. 6pm
- D. 7pm Discuss
- 9. If 60% of 35 of a number is 36, then the number is
Options- A. 86
- B. 94
- C. 100
- D. 115 Discuss
- 10. 476 ** 0 is divisible by both 3 and 11.The non zero digits in the hundred's and ten's places are respectively:
Options- A. 6 and 2
- B. 8 and 2
- C. 6 and 5
- D. 8 and 5 Discuss
More questions
Correct Answer: 24min
Explanation:
In this type of problems the formuae is
(5*x+ or - t)*12/11
Here x is replaced by the first interval of given time. Here x is 5.
t is spaces apart
Case 1 : (5*x + t) * 12/11
(5*5 + 3) * 12/11
28 * 12/11 = 336/11= min
therefore the hands will be 3 min apart at 31 5/11 min past 5.
Case 2 : (5*x - t) * 12/11
(5*5 -3 ) * 12/11
22 *12/11 = 24 min
therefore the hands will be 3 min apart at 24 min past 5
Correct Answer: 60
Correct Answer: 75
Explanation:
Let Divisor be x. We know that Dividend = Remainder+Divisor×Quotient So Divisor = (Dividend - Remainder)/Quotient ⇒ x = (4150 - 25)/55 ⇒ x = 4125/55 ⇒ x = 75 Hence Divisor is 75.
Correct Answer: (10 + 10/11) min past 2
Correct Answer: 4/5
Explanation:
Let the required fraction be x. Then, (1 / x )- x = 9/20
1 - x^(2) / x = 9 / 20 => 20 - 20 * x^(2) = 9 * x.
20 * x^(2) + 9 *x - 20 = 0.
=> (4 * x + 5) (5 * x - 4) = 0.
=> x = 4 / 5.
Correct Answer: 9
Explanation:
The sum of three consecutive integers can be written as n + (n + 1) + (n + 2) = 3n + 3
If the sum is 24, we need to solve the equation 3n + 3 = 24;
=> 3n = 21;
=> n = 7
The greatest of the three numbers is therefore 7 + 2 = 9
Correct Answer: 67.5 degrees
Correct Answer: 4pm
Correct Answer: 100
Explanation:
Let the number be x.Then
60% of of x=36.
=>
=> => x=
Required number is 100.
Correct Answer: 8 and 5
Explanation:
Let the number be 476ab0
476ab0 is divisible by 3
=> 4 + 7 + 6 + a + b + 0 is divisible by 3
=> 17 + a + b is divisible by 3 ------------------------(i)
476ab0 is divisible by 11
[(4 + 6 + b) -(7 + a + 0)] is 0 or divisible by 11
=> [3 + (b - a)] is 0 or divisible by 11 --------------(ii)
Substitute the values of a and b with the values given in the choices and select the values which satisfies both Equation 1 and Equation 2.
if a=6 and b=2,
17 + a + b = 17 + 6 + 2 = 25 which is not divisible by 3 --- Does not meet equation(i).Hence this is not the answer
if a=8 and b=2,
17 + a + b = 17 + 8 + 2 = 27 which is divisible by 3 --- Meet equation(i)
[3 + (b - a)] = [3 + (2 - 8)] = -3 which is neither 0 nor divisible by 11---Does not meet equation(ii).Hence this is not the answer
if a=6 and b=5,
17 + a + b = 17 + 6 + 5 = 28 which is not divisible by 3 --- Does not meet equation (i) .Hence this is not the answer
if a=8 and b=5,
17 + a + b = 17 + 8 + 5 = 30 which is divisible by 3 --- Meet equation 1
[3 + (b - a)] = [3 + (5 - 8)] = 0 ---Meet equation 2
Since these values satisfies both equation 1 and equation 2, this is the answer
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