can you explain this? i did lost of multiplying... dividing of fractions... getting confused... improper fractions... D. all of the above and had no such luck

Thanks

money9111 wrote:can you explain this? i did lost of multiplying... dividing of fractions... getting confused... improper fractions... D. all of the above and had no such luck

Thanks

I am providing solution of this problem for reference. But please try it once yourself and then check out for solution.
Well a certain hint is try LCM

[spoiler]First watch ticks after 95/90 seconds.
second watch after 323/315 seconds.
LCM = 19*5*17/45 seconds.
No. of times they will tick in first 3600 seconds = 3600/(19*5*17)/45
Once they have ticked together in the begining , 50 in 1 hour they tick 100+1 = 101 times[/spoiler]

how is 19*5*17 the LCM? I went down to Prime Factors, but I had 2,3,3,5,7

money9111 wrote:how is 19*5*17 the LCM? I went down to Prime Factors, but I had 2,3,3,5,7

Factoring the numerator only...

95 factors to (5, 19)
323 factors to (17, 19)

So the LCM is 5*17*19

aaaahhh i see... i flubbed up the fractions... had it the other way around... ok thanks I get it

money9111 wrote:how is 19*5*17 the LCM? I went down to Prime Factors, but I had 2,3,3,5,7

It is quite simple money1119 ...
95 = 19 x 5
323 = 17 x 19
so LCM = 17 x 19 x5

then what is the problem in this.. ?????????? I have provided you with whole solution...

no when you said numerator you threw me off because my numerator and denominators were the opposite of yours... so i understand it now..you DID explain it correctly, but as I was looking at what I wrote down... i noticed i messed up the initial set up