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Q:

# At what time between 4 and 5 o'clock will the hands of a watch point in opposite directions?

 A) 54 past 4 B) (53 + 7/11) past 4 C) (54 + 8/11) past 4 D) (54 + 6/11) past 4

Answer:   D) (54 + 6/11) past 4

Explanation:

4 o'clock, the hands of the watch are 20 min. spaces apart.
To be in opposite directions, they must be 30 min. spaces apart.
$\inline \therefore$Minute hand will have to gain 50 min. spaces.
55 min. spaces are gained in 60 min

50 min. spaces are gained in $\inline (\frac{60}{55}\times 50)$ min. or $\inline 54\frac{6}{11}$

$\inline \therefore$ Required time = $\inline 54\frac{6}{11}$ min. past 4.

Q:

A watch gains 5 seconds in 3 minutes and was set right at 8 AM. What time will it show at 10 PM on the same day ?

 A) 10 : 27 : 41 AM B) 8 : 51 : 04 AM C) 9 : 45 : 15 PM D) 10 : 23 : 20 PM

Explanation:

The watch gains 5 seconds in 3 minutes = 100 seconds in 1 hour.

From 8 AM to 10 PM on the same day, time passed is 14 hours.

In 14 hours, the watch would have gained 1400 seconds or 23 minutes 20 seconds.

So, when the correct time is 10 PM, the watch would show 10 : 23 : 20 PM

3 137
Q:

How many degrees will the minute hand move, in the same time in which the second hand move 5400 ?

 A) 90 degrees B) 85 degrees C) 60 degrees D) 45 degrees

Explanation:

Minute hand covers 5400/60 = 90°

3 79
Q:

In 16 minutes, the minute hand gains over the hour hand by -

 A) 16 deg B) 80 deg C) 88 deg D) 94 deg

Explanation:

In one hour, the minute hand gains 330° over the hour hand. i.e., 60 minute, the minute hand gains 330° over the hour hand.

∴ In 16 minutes, the minute hand gain over the hour hand by

3 117
Q:

At 6′o clock a clock ticks 6 times. The time between first and last ticks is 30 seconds. How long does it tick at 12′o clock ?

 A) 66 sec B) 55 sec C) 36 sec D) 24 sec

Explanation:

For ticking 6 times, there are 5 intervals.

Each interval has time duration of 30/5 = 6 secs

At 12 o'clock, there are 11 intervals,
so total time for 11 intervals = 11 x 6 = 66 secs.

4 256
Q:

At what time between 3 and 4 o’clock will the minute hand and the hour hand are on the same straight line but facing opposite directions ?

 A) 3:15 2/8 B) 3:49 C) 3:49 1/11 D) 3:51

Explanation:

On straight line means 180 degree angle.
180 = 11/2 min – 30 hrs
180 = 11/2 m – 30 × 3
180 = 11/2 m – 90
(180 + 90) 2 = 11 m
m = 540/11 = 49 1/11 minutes.

$\inline \fn_jvn \therefore time = 3: 49 \frac{1}{11}$