[B].
[C].
[D].
Answer: Option C
Explanation:
| Other number = | 11 x 7700 | = 308. | ||
| 275 |
| 3 |
| 4 |
[B].
| 4 |
| 7 |
[C].
| 1 |
| 8 |
[D].
| 3 |
| 7 |
Answer: Option B
Explanation:
Let number of balls = (6 + 8) = 14.
Number of white balls = 8.
| P (drawing a white ball) = | 8 | = | 4 | . |
| 14 | 7 |
[B].
[C].
[D].
Answer: Option B
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 |
[B].
[C].
[D].
Answer: Option B
Explanation:
| Speed = | 54 x | 5 | m/sec = 15 m/sec. | |
| 18 |
Length of the train = (15 x 20)m = 300 m.
Let the length of the platform be x metres.
| Then, | x + 300 | = 15 |
| 36 |
x + 300 = 540
x = 240 m.
[B].
[C].
[D].
Answer: Option B
Explanation:
Let the required number of revolutions made by larger wheel be x.
Then, More cogs, Less revolutions (Indirect Proportion)
14 : 6 :: 21 : x 14 x x = 6 x 21
| x = | 6 x 21 |
| 14 |
x = 9.
[B].
[C].
[D].
Answer: Option A
Explanation:
Let the speed of the stream x mph. Then,
Speed downstream = (10 + x) mph,
Speed upstream = (10 – x) mph.
| 36 | – | 36 | = | 90 | |
| (10 – x) | (10 + x) | 60 |
72x x 60 = 90 (100 – x2)
x2 + 48x – 100 = 0
(x+ 50)(x – 2) = 0
x = 2 mph.