What is the smallest five digit number that is divisible by 15, 36, 40, and 54?
Options:  A) 10400  B) 10800  C) 11200  D) 11600  E) 12000
15 = 3 * 5   36 = 2^2 * 3^2   40 = 2^3 * 5   54 = 2 * 3^3   LCM = 2^3 * 3^3 * 5 = 1080   The smallest five-digit number that is a multiple of 1080 is 10*1080 = 10,800   The answer is 10800.
<result>B</result>
What is the smallest five digit number that is divisible by 15, 36, 40, and 54?