What is the greatest value of positive integer x such that 2^x is a factor of 100^40? Select: A) 80 B) 90 C) 95 D) 105 E) 110
Put in simple words, we need to find the highest power of 2 in 100^40   100 = 2^2*5^2   Therefore 100^40 = (2^2*5^2)^40 = 2^80*5^80   80nswer : 80
<result>A</result>
What is the greatest value of positive integer x such that 2^x is a factor of 100^40?