Aptitude - Clock - Discussion
Discussion Forum : Clock - General Questions (Q.No. 4)
4.
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:
Answer: Option
Explanation:
| Time from 7 a.m. to 4.15 p.m. = 9 hrs 15 min. = | 37 | hrs. |
| 4 |
3 min. 5 sec. of this clock = 3 min. of the correct clock.
 |
37 | hrs of this clock = | 1 | hrs of the correct clock. |
| 720 | 20 |
| |
37 | hrs of this clock = |  |
1 | x | 720 | x | 37 |  |
hrs of the correct clock. |
| 4 | 20 | 37 | 4 |
= 9 hrs of the correct clock.
The correct time is 9 hrs after 7 a.m. i.e., 4 p.m.
Discussion:
156 comments Page 16 of 16.
Dhanush said:
2 years ago
For 3 mins it gains 5 seconds.
Then for 925 minutes (9hr 15 min) it gains 15 mins 25 seconds.
So, subtract 15 mins 25 seconds from 4:15.
We will get 3:59:35 which is 59* (7/12) mins past 3.
Then for 925 minutes (9hr 15 min) it gains 15 mins 25 seconds.
So, subtract 15 mins 25 seconds from 4:15.
We will get 3:59:35 which is 59* (7/12) mins past 3.
(35)
Khairul Basar said:
2 years ago
Gain:
3 minutes 5 sec,
15 minutes 25 sec,
30 minutes 50 sec,
60 min( 1 hour) 100 sec.
Then, 7 to 4:15 - 9 hours 15 minutes.
Per hour 100 sec= 900.
And 15 minutes 25 sec.
Total - 925 sec.
925 sec ÷ 60 = 15 minutes.
(15 mins is extra).
9 hours 15 - 15 minutes 9 hours.
7 AM to 4 PM (9 hours).
So, the answer is 4 PM.
3 minutes 5 sec,
15 minutes 25 sec,
30 minutes 50 sec,
60 min( 1 hour) 100 sec.
Then, 7 to 4:15 - 9 hours 15 minutes.
Per hour 100 sec= 900.
And 15 minutes 25 sec.
Total - 925 sec.
925 sec ÷ 60 = 15 minutes.
(15 mins is extra).
9 hours 15 - 15 minutes 9 hours.
7 AM to 4 PM (9 hours).
So, the answer is 4 PM.
(104)
Pumpkin pieeeeee said:
1 year ago
The answer is A.
A lot of people are ignoring the extra 25 seconds.
The exact time gained is 925 seconds.
(This is best explained in the comment down below)
900 seconds is 15 minutes. So, we deduct 15 minutes from the time given.
ADDITIONALLY, 25 seconds also will be deducted -
60 - 25 = 35 seconds remaining.
Hence, 35/60 which explains the extra 7/12.
The final answer is -> 59 7/12 minutes past 3.
A lot of people are ignoring the extra 25 seconds.
The exact time gained is 925 seconds.
(This is best explained in the comment down below)
900 seconds is 15 minutes. So, we deduct 15 minutes from the time given.
ADDITIONALLY, 25 seconds also will be deducted -
60 - 25 = 35 seconds remaining.
Hence, 35/60 which explains the extra 7/12.
The final answer is -> 59 7/12 minutes past 3.
(23)
Usha said:
1 year ago
I think 59 (7/12) past 3.
So, Option A is correct.
So, Option A is correct.
(19)
MOHITH said:
2 months ago
THE CORRECT ANSWER IS OPTION(A)
Step 1: Find total gain per minute
Given: 5 sec gain in 3 min
Gain per minute = 5/3 sec
Step 2: Find total time shown by watch
From 7:00 a.m. to 4:15 p.m. = 555 minutes
Step 3: Find total gain in that time,
Total gain = 555 × 5/3.
= 925 sec.
Convert:
925 sec = 15 min 25 sec.
Step 4: Subtract gain from shown time,
Watch is fast, so:
Real time=4:15−15 min 25 sec.
= 3:59:35 p.m.
converting to mixed fraction give us answer as 3:59:35/60 that is equals to 3:59:7/12.
Step 1: Find total gain per minute
Given: 5 sec gain in 3 min
Gain per minute = 5/3 sec
Step 2: Find total time shown by watch
From 7:00 a.m. to 4:15 p.m. = 555 minutes
Step 3: Find total gain in that time,
Total gain = 555 × 5/3.
= 925 sec.
Convert:
925 sec = 15 min 25 sec.
Step 4: Subtract gain from shown time,
Watch is fast, so:
Real time=4:15−15 min 25 sec.
= 3:59:35 p.m.
converting to mixed fraction give us answer as 3:59:35/60 that is equals to 3:59:7/12.
(2)
DRB said:
4 weeks ago
@All.
To those who say option A is correct.
1. Total minutes as per the time shown by the watch from 7.00 am to 4.15 pm
555 minutes.
(these 555 minutes also include the 5 sec. gained by the watch every 3 minutes.
Most people have failed to adjust to the same.)
2. Let's see how to adjust to nullify the 5 seconds gained every three minutes to arrive at the correct answer.
Every three minutes, the watch gains 5 seconds.
3 minutes = 180 seconds.
So, 555minutes * 180/185 =540 minutes.
NOTE: This step can be solved in many different ways. for eg, instead of converting 3 minutes in 180 seconds, you can keep them as it is and instead say gains per minute is 1.66666667 seconds. etc.
3. Final answer 7.00 am + 540 minutes = 4.00 pm.
To those who say option A is correct.
1. Total minutes as per the time shown by the watch from 7.00 am to 4.15 pm
555 minutes.
(these 555 minutes also include the 5 sec. gained by the watch every 3 minutes.
Most people have failed to adjust to the same.)
2. Let's see how to adjust to nullify the 5 seconds gained every three minutes to arrive at the correct answer.
Every three minutes, the watch gains 5 seconds.
3 minutes = 180 seconds.
So, 555minutes * 180/185 =540 minutes.
NOTE: This step can be solved in many different ways. for eg, instead of converting 3 minutes in 180 seconds, you can keep them as it is and instead say gains per minute is 1.66666667 seconds. etc.
3. Final answer 7.00 am + 540 minutes = 4.00 pm.
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