Question

A clock strikes once at 1 oclock twice at 2 o clock thrice at 3 o clock how many times will it strike in 9 hours

Answer 1

Answer:

45 TIMES...

Step-by-step explanation:

a clock strikes once at 1 o' clock , twice at 2 o' clock and so on. We have to find out number of strikes in a day .

clock strikes serially , 1 , 2 , 3, 4 , .... 9

here what you observed?

all are in AP because common difference is always 1 .

Now, use sum of n natural number = n(n+1)/2

Here, n = 9

So,9(9+1)/2

=(9×10)/2

=90/2

=45 times

HOPE THIS HELPS YOU..

MARK ME AS BRAINLIEST....

Answer 2

Answer:

9 times

Step-by-step explanation: