The sum of positive integers x and y is 77. What is the value of xy?
(1) x = y + 1
(2) x and y have the same tens digit.
A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is
sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.
Answer:

MINE A

ANS D

请指教!

D。因为B成立，由B知道X和Y只能为38和39。

(2) x and y have same 10th digit, if x = 30, y = 37, or if x = 32, y = 35... then product of xy will have multiple values.

I lean to A. Please advise.

支持D