题目:
lf x, y, and z are three-digit positive integers and if x = y+ z, iS the hundreds digit of x equal to the sum of the hundreds digits of y and z ?
(1) The tens digit of x is equal to the sum of the tens digits of y and z.
(2) The units digit of x is equal to the sum of the units digits of y and z.
选项:
答案:
A