SAT官方每日一题附答案和解析[数学](2014年12月12日)
日期:2014-12-12 13:40
(单词翻译:单击)
每日一题
Mathematics>Standard Multiple Choice
Read the following SAT test question and then click on a button to select your answer.
What is the largest possible integer value of n for which 5^n divides 50^7?
(A) 2
(B) 7
(C) 9
(D) 10
(E) 14
答案和解析
答案:E
解析:
Choice (E) is correct. Since 50 = 2 times 5^2, it follows that 50^7= (2 times 5^2)^7. Applying the laws of exponents to the preceding equality yields 50^7 = (2^7) times (5^14). From this representation of 50^7, it follows that 5^14divides 50^7 and that 14 is the largest value of n for which 5^n divides 50^7.