list all the odd number which are multiples of 5
105 = 5
115 = 5
125 = 5*5*5
135 = 5
145 = 5
155 = 5
165 = 5
175 = 5*5
185 = 5
195 = 5
k = 13
I was able to this in less than 2 mins but any shorter way would be helpful.
integer, factor, odd number, power...
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parallel_chase
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, could u please expalin wat is that we trtying to find coz it says product of odd number so i felt 105*110*so on ...-
parallel_chase
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The question stem says:
product of odd numbers from 99 to 199 i.e.
99*101*103*105*107*.......*199 has how many factors of 5
Hope its clear now.
product of odd numbers from 99 to 199 i.e.
99*101*103*105*107*.......*199 has how many factors of 5
Hope its clear now.
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sudhir3127
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I have different method..parallel_chase wrote:list all the odd number which are multiples of 5
105 = 5
115 = 5
125 = 5*5*5
135 = 5
145 = 5
155 = 5
165 = 5
175 = 5*5
185 = 5
195 = 5
k = 13
I was able to this in less than 2 mins but any shorter way would be helpful.
here it goes..
99- 199. number of odd numbers are 51
thus number of 5's are
51/5 + 51/5^2 = 12 but 125 will have 5^3 so need t take one more 5
thus its 12 + 1 =13.
hope it helps..
