Question

A clock moves 10 sec ahead every 10 min. The time was set at 7:00 a.m. What
time will the clock show at 10:00 night?
​

Answer 1

Answer: 10:15 p.m

It is given that a clock moves 10 seconds ahead after every minutes passes. which means, If It's currently 8:00:10 a.m , At 8:10:10 a.m, This clock will show 8:10:20 a.m.

Notice the seconds are not same in each case (difference of 10 seconds as stated in the question)

Now, we are asked what would the clock show at actual 10:00 night or 10:00 p.m. Initially, the timing in the clock is 7:00 a.m (7'O clock in the morning).

First, we should find the time difference between the two given time. After that we would find the increment in the timing of the given clock. And add the incremented time to the actual time to get the answer.

Time Difference:

⇒ ∆T = (7:00 a.m - 10:00 p.m)

Convert the timing into 24 hour format, we get

⇒ ∆T = 7:00 - 22:00

⇒ ∆T = 22 - 7

⇒ ∆T = 15 hours

Now, Let's find the increment in the time according to the clock,

⇒ In 10 minutes ➞ Increment in time 10 s

Divide both sides to find the increment after every hour.

⇒ In 10/60 hour ➞ Increment in time 10/60 min

⇒ In 1/6 hour ➞ Increment in time 1/6 min

Multiply both sides by 6 to get only integers,

⇒ In 1 hour ➞ Increment in time is 1 min

So, After 15 hours

⇒ Increment in time will be 15×1 = 15 minutes

Which means after 15 hours, the clock will be 15 minutes ahead of the actual time.

Hence, At 10:00 p.m the clock will show 10:15 p.m

Answer 2

${ \red{ \underline{ \underline{ \tt{ \huge{QUESTION}}}}}} :$

• A clock moves 10 sec ahead every 10 min. The time was set at 7:00 a.m. What time will the clock show at 10:00 night?

${ \red{ \underline{ \underline{ \tt{ \huge{TO \: \: FIND}}}}}} :$

• What time will the clock show at 10:00 night?

${ \red{ \underline{ \underline{ \tt{ \huge{SOLUTION}}}}}} :$

Given ,

• Clock moves 10 sec forward for every minute.

Then ,

We have to find the time between 7 : 00 : 00 a.m to 10 : 00 : 00 p.m:-

${ \sf{ \blue{\implies { Time = 22 - 7 }}}}$

${ \sf{ \blue{\implies { Time = 15 hours }}}}$

Here ,

${ \sf{ \blue{\implies { Increment = 15 \times 1}}}}$

${ \sf{ \blue{\implies { Increment = 15 }}}}$

Hence ,

• The time shown at 10 p.m is 10 : 15 p.m