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February 17th, 2018, 06:01 PM   #1
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How to solve this problem regarding clock strikes?

Question: A clock strikes once at 1:00 Clock and twice at 2:00 clock, thrice at 3:00 clock, and so on, respectively. How many total strikes per day?

Solution: 1 + 2 + 3 + 4.........+ 12

= 12(13)/2

= 78 × 2 = 156 (Answer)

My doubt - how can a clock hits "once at 1:00 clock" if 1:00 clock happens twice per day, i.e. 1 am and 1 pm?

Last edited by skipjack; February 17th, 2018 at 06:52 PM.
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February 17th, 2018, 06:12 PM   #2
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When the clock shows one it strikes once, be it am or pm.
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February 18th, 2018, 01:11 AM   #3
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Quote:
Originally Posted by greg1313 View Post
When the clock shows one it strikes once, be it am or pm.
I think you misunderstood the question, In my question there is also a sentence
which says " twice at 2:00 clock, thrice at 3:00 clock". if you say "When the clock shows one it strikes once, be it am or pm." then it is impossible to twice at 2:00 clock, thrice at 3:00 clock.

Are you saying question is wrong?
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February 18th, 2018, 01:44 AM   #4
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Quote:
Originally Posted by Ganesh Ujwal View Post
A clock strikes once at 1:00 Clock and twice at 2:00 clock, thrice at 3:00 clock...
At one pm the clock strikes once. At one am the clock strikes once. A two pm the clock strikes twice. At two am the clock strikes twice. At three pm the clock strikes thrice. At three am the clock strikes thrice. And so on.
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February 18th, 2018, 02:08 AM   #5
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Quote:
Originally Posted by greg1313 View Post
At two am the clock strikes twice.
How ? you mean shorter hand at 2 and longer hand at 12. which shows twice?
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February 18th, 2018, 02:10 AM   #6
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The clock chimes twice! Google "definition of chime" if you don't know what that means.
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Last edited by greg1313; February 18th, 2018 at 02:14 AM.
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February 18th, 2018, 02:29 AM   #7
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Solution: 1 + 2 + 3 + 4.........+ 12

= 12(13)/2

= 78 × 2 = 156 (Answer)

Why they multiple with 13 and divided with 2.

Last edited by Ganesh Ujwal; February 18th, 2018 at 02:42 AM.
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February 18th, 2018, 02:56 AM   #8
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The average of the first and last term is (1 + 12)/2 = 13/2.

The sum is 12 (the number of terms) multiplied by the above average.
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February 18th, 2018, 03:05 AM   #9
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Quote:
Originally Posted by skipjack View Post
The average of the first and last term is (1 + 12)/2 = 13/2.

The sum is 12 (the number of terms) multiplied by the above average.
Why did you bring average concept suddenly ?
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February 18th, 2018, 04:14 AM   #10
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Quote:
Originally Posted by Ganesh Ujwal View Post
My doubt - how can a clock hits "once at 1:00 clock" if 1:00 clock happens twice per day, i.e. 1 am and 1 pm?
That obviously means "hits 1 time at 1a.m. and 1 time at 1p.m."

Ding dong!
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