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- Question
Some children goto ice-cream shop. 9 flavours are available there. Each child takes a cone with two different flavours. No two children take same combination and they have taken all such possible combinations. How many children went to ice cream shop ?
Options- A. 28
- B. 56
- C. 44
- D. 36
- Correct Answer
- 36
ExplanationGiven there are 9 flavours of ice creams.
Each child takes the combination of two flavours and no two children will have the same combination
This can be done by ways i.e children.
Number of children= = 9 x 8 / 1x 2 = 36.
- 1. A certain distance is covered at a certain speed. If half of this distance is covered in double the time, the ratio of the two speed is?
Options- A. 4:1
- B. 1.4
- C. 2:1
- D. 1:2 Discuss
- 2. The length of the train that takes 8 second to pass a pole where it runs at a speed of 36 km/hr is?
Options- A. 288 meters
- B. 45 meters
- C. 48 meters
- D. 80 meters Discuss
- 3. Two goods train each 500 m long, are running in opposite directions on parallel tracks. Their speeds are 45 km/hr and 30 km/hr respectively. Find the time taken by the slower train to pass the driver of the faster one.
Options- A. 12 sec
- B. 24 sec
- C. 48 sec
- D. 60 sec Discuss
- 4. A jogger running at 9 kmph alongside a railway track in 240 metres ahead of the engine of a 120 metres long train running at 45 kmph in the same direction. In how much time will the train pass the jogger?
Options- A. 3.6 sec
- B. 18 sec
- C. 36 sec
- D. 72 sec Discuss
- 5. A train 108 m long moving at a speed of 50 km/hr crosses a train 112 m long coming from opposite direction in 6 seconds. The speed of the second train is:
Options- A. 48 km/hr
- B. 54 km/hr
- C. 66 km/hr
- D. 82 km/hr Discuss
- 6. Two stations A and B are 110 km apart on a straight line. One train starts from A at 7 a.m. and travels towards B at 20 kmph. Another train starts from B at 8 a.m. and travels towards A at a speed of 25 kmph. At what time will they meet?
Options- A. 9 a.m.
- B. 10 a.m.
- C. 10.30 a.m.
- D. 11 a.m. Discuss
- 7. Two goods train each 500 m long, are running in opposite directions on parallel tracks. Their speeds are 45 km/hr and 30 km/hr respectively. Find the time taken by the slower train to pass the driver of the faster one.
Options- A. 12 sec
- B. 24 sec
- C. 48 sec
- D. 60 sec Discuss
- 8. When a plot is sold for Rs. 18,700, the owner loses 15%. At what price must that plot be sold in order to gain 15%?
Options- A. Rs. 21,000
- B. Rs. 22,500
- C. Rs. 25,300
- D. Rs. 25,800 Discuss
- 9. If x and y are the two digits of the number 653xy such that this number is divisible by 80, then x + y =?
Options- A. 2 or 6
- B. 4
- C. 4 or 8
- D. 8
- E. None of these Discuss
- 10. The difference of the squares of two consecutive odd integers is divisible by which of the following integers?
Options- A. 3
- B. 6
- C. 7
- D. 8 Discuss
More questions
Correct Answer: 4:1
Explanation:
Let x km . be covered in y hrs.
then, 1st speed = (x / y) km/hr.
2nd speed = [(x/2) / 2y)] km/hr.
= (x/4y) km/hr.
? Ratio of speed = x/y : x/4y = 1 :1/4 = 4: 1
Correct Answer: 80 meters
Explanation:
Speed of the train = (36 x 5)/18 = 10 m/sec.
Distance = (Time x Speed ) = (8 x 10 ) = 80 meters
? Length of the train = 80 meters
Correct Answer: 24 sec
Explanation:
| Relative speed = | = (45 + 30) km/hr | |||||||
|
||||||||
|
We have to find the time taken by the slower train to pass the DRIVER of the faster train and not the complete train.
So, distance covered = Length of the slower train.
Therefore, Distance covered = 500 m.
| ∴ Required time = | ❨ | 500 x | 6 | ❩ | = 24 sec. |
| 125 |
Correct Answer: 36 sec
Explanation:
Speed of train relative to jogger = (45 - 9) km/hr = 36 km/hr.
| = | ❨ | 36 x | 5 | ❩m/sec |
| 18 |
= 10 m/sec.
Distance to be covered = (240 + 120) m = 360 m.
Correct Answer: 82 km/hr
Explanation:
Let the speed of the second train be x km/hr.
| Relative speed | = (x + 50) km/hr | |||||||
|
||||||||
|
Distance covered = (108 + 112) = 220 m.
| ∴ | 220 | = 6 | ||
|
⟹ 250 + 5x = 660
⟹ x = 82 km/hr.
Correct Answer: 10 a.m.
Explanation:
Suppose they meet x hours after 7 a.m.
Distance covered by A in x hours = 20x km.
Distance covered by B in (x - 1) hours = 25(x - 1) km.
∴ 20x + 25(x - 1) = 110
⟹ 45x = 135
⟹ x = 3.
So, they meet at 10 a.m.
Correct Answer: 24 sec
Explanation:
| Relative speed = | = (45 + 30) km/hr | |||||||
|
||||||||
|
We have to find the time taken by the slower train to pass the DRIVER of the faster train and not the complete train.
So, distance covered = Length of the slower train.
Therefore, Distance covered = 500 m.
| ∴ Required time = | ❨ | 500 x | 6 | ❩ | = 24 sec. |
| 125 |
Correct Answer: Rs. 25,300
Explanation:
85 : 18700 = 115 : x
| ⟹ x = | ❨ | 18700 x 115 | ❩ | = 25300. |
| 85 |
Hence, S.P. = Rs. 25,300.
Correct Answer: 2 or 6
Explanation:
80 = 2 x 5 x 8
Since 653xy is divisible by 2 and 5 both, so y = 0.
Now, 653x is divisible by 8, so 13x should be divisible by 8.
This happens when x = 6.
∴x + y = (6 + 0) = 6.
Correct Answer: 8
Explanation:
Let the two consecutive odd integers be (2 n + 1) and (2 n + 3). Then,
(2n + 3)2 - (2n + 1)2 = (2n + 3 + 2n + 1) (2n + 3 - 2n - 1)
= (4n + 4) x 2
= 8(n + 1), which is divisible by 8.
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