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- Question
A boat running upstream takes 8 hours 48 minutes to cover a certain distance, while it takes 4 hours to cover the same distance running downstream. What is the ratio between the speed of the boat and speed of the water current respectively?
Options- A. 7:4
- B. 11:4
- C. 4:7
- D. 8:3
- Correct Answer
- 8:3
ExplanationLet the speed of the boat upstream be p kmph and that of downstream be q kmph
Time for upstream = 8 hrs 48 min = hrs
Time for downstream = 4 hrs
Distance in both the cases is same.
=> p x = q x 4
=> 44p/5 = 4q
=> q = 11p/5
Now, the required ratio of Speed of boat : Speed of water current
=
=> (11p/5 + p)/2 : (11p/5 - p)/2
=> 8 : 3
- 1. If 0.764 x P = 1.236 x Q, then what is the value of (Q - P) / (Q + P)?
Options- A. 0.764
- B. 0.236
- C. 2
- D. 0.472 Discuss
- 2. In a two-digit, if it is known that its unit's digit exceeds its ten's digit by 2 and that the product of the given number and the sum of its digits is equal to 144, then the number is:
Options- A. 24
- B. 26
- C. 42
- D. 46 Discuss
- 3. On dividing a certain number by 357, the remainder is 39. On dividing the same number by 17, what will be the remainder?
Options- A. 5
- B. 3
- C. 7
- D. 6 Discuss
- 4. A man complete a journey in 10 hours. He travels first half of the journey at the rate of 21 km/hr and second half at the rate of 24 km/hr. Find the total journey in km.
Options- A. 220 km
- B. 224 km
- C. 230 km
- D. 234 km Discuss
- 5. If a pipe fills a tank in 6 h, then what part of the tank will the pipe fill in 1 h?
Options- A. 1/3
- B. 1/6
- C. 1/4
- D. 1/5 Discuss
- 6. A number consists of 3 digits whose sum is 10. The middle digit is equal to the sum of the other two and the number will be increased by 99 if its digits are reversed. The number is:
Options- A. 145
- B. 253
- C. 370
- D. 352 Discuss
- 7. 8597 -? = 7429 - 4358
Options- A. 5426
- B. 5706
- C. 5526
- D. 5476
- E. None of these Discuss
- 8. A cistern is normally filled in 8 hours but takes two hours longer to fill because of a leak in its bottom. If the cistern is full, the leak will empty it in?
Options- A. 16 hrs.
- B. 20 hrs.
- C. 25 hrs.
- D. 40 hrs. Discuss
- 9. 20 persons were invited to a party. In how many ways, they and the host can be seated at a circular table?
Options- A. 18 !
- B. 19 !
- C. 20 !
- D. Couldn't be determined Discuss
- 10. An outlet pipe can empty a cistern in 3 h. In what time will the pipe empty two-third part of the cistern?
Options- A. 4 h
- B. 2 h
- C. 3 h
- D. 5 h Discuss
More questions
Correct Answer: 0.236
Explanation:
Given, 0.764 x P = 1.236 x Q
? Q / P = 1.236 / 0.764
Now, (Q - P) / (Q + P) = [(Q/P) - 1] / [(Q/P) + 1]
? [(1.236/0.764) - 1] / [(1.236/0.764) + 1]
= (1.236 - 0.764) / (1.236 + 0.764)
= 0.472 / 2.000
= 0.236
Correct Answer: 24
Explanation:
Then, unit's digit = x + 2.
Number = 10x + (x + 2) = 11x + 2.
Sum of digits = x + (x + 2) = 2x + 2.
∴ (11x + 2)(2x + 2) = 144
⟹ 22x2 + 26x - 140 = 0
⟹ 11x2 + 13x - 70 = 0
⟹ (x - 2)(11x + 35) = 0
⟹ x = 2.
Hence, required number = 11x + 2 = 24.
Correct Answer: 5
Explanation:
Let the given number be N
Therefore N = 357k + 39
Then,
357 k + 39 = ( 17 x 21k ) + ( 17 x 2 ) + 5
? Required remainder = 5
Correct Answer: 224 km
Explanation:
| (1/2)x | + | (1/2)x | = 10 |
| 21 | 24 |
| ⟹ | x | + | x | = 20 |
| 21 | 24 |
⟹ 15x = 168 x 20
| ⟹ x = | ❨ | 168 x 20 | ❩ | = 224 km. |
| 15 |
Correct Answer: 1/6
Explanation:
We know that, when a pipe fills a tank in m h, then the part of tank filled in 1 h = 1/m
Here, m = 6
? Required part of the tank to be filled in 1h = 1/6 part
Correct Answer: 253
Explanation:
Then, 2x = 10 or x = 5. So, the number is either 253 or 352.
Since the number increases on reversing the digits, so the hundred's digits is smaller than the unit's digit.
Hence, required number = 253.
Correct Answer: 5526
Explanation:
7429 Let 8597 - x = 3071 -4358 Then, x = 8597 - 3071 ---- = 5526 3071 ----
Correct Answer: 40 hrs.
Explanation:
Work done by leak in 1 hour = (1/8 - 1/10) = 1/40
? The leak will empty the cistern in 40 hours.
Correct Answer: 20 !
Explanation:
Total persons on the circular table
= 20 guests + 1 host = 21
They can be seated in (21 - 1) ! = 20 ! ways .
Correct Answer: 2 h
Explanation:
Time taken by the pipe to empty the cistern = 3 h
Then, time taken by the pipe to empty the 2/3 part = 3 x 2/3 = 2 h
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