prep2两题请指教--急,26th考.

ktj

80.  If x and y are positive integers such that x = 8y + 12, what is the greatest common divisor of x and y ? 

(1) x = 12u, where u is an integer.

(2) y = 12z, where z is an integer. 

答案B. 如何推导

47, In the fraction x/y, where x and y are positive integers, what is the value of y ?

(1),the least common denominator of x/y and 1/3 is 6

(2),x=1

答案E.. 不懂兰色部分什么意思!

 

 

(1),the least common denominator of x/y and 1/3 is 6

(2),x=1

答案E.. 不懂兰色部分什么意思!