WORD PROBLEM

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WORD PROBLEM

by sayanpaul » Mon May 06, 2013 10:37 pm
A certain clock rings two notes at quarter past the hour, four notes at half past and six notes at three-quarters past. On the hour, it rings eight notes plus an additional number of notes equal to whatever hour it is. How many notes will the clock ring between 1:00 pm and 5:00 pm including the rings at 1:00 and 5:00 ?

A.87
B.95
C.102
D.103
E.115
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by hemant_rajput » Mon May 06, 2013 11:11 pm
sayanpaul wrote:A certain clock rings two notes at quarter past the hour, four notes at half past and six notes at three-quarters past. On the hour, it rings eight notes plus an additional number of notes equal to whatever hour it is. How many notes will the clock ring between 1:00 pm and 5:00 pm including the rings at 1:00 and 5:00 ?

A.87
B.95
C.102
D.103
E.115

Image

at 1:00 - 8 + 1
b/w 1-2 + at 2:00 - 20 + 2
b/w 2-3 + at 3:00 - 20 + 3
b/w 3-4 + at 4:00 - 20 + 4
b/w 4-5 + at 5:00 - 20 + 5

total = 88 + 15 = 103

D
Last edited by hemant_rajput on Tue May 07, 2013 1:15 am, edited 2 times in total.
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by aaggar7 » Tue May 07, 2013 12:00 am
Lets first get the count for 15 mins,30 mins,45 mins ring.

1-2 2 + 4 + 6 =12
2-3 =12
3-4 =12
4-5 =12

Total 48

Now lets calculate at each hour

1 8 + 1 = 9
2 = 10
3 = 11
4 = 12
5 = 13

= 55

So total rings = 48 + 55 = 103

hence D

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by hemant_rajput » Tue May 07, 2013 1:16 am
I've edited my post for the mistake pointed by aagar7
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by sayanpaul » Tue May 07, 2013 2:00 am
thats right, the answer is 103.