If positive integer x is a multiple of 6 and positive integer y is a multiple of 14,is xy a multiple of 105?(1) x is a multiple of 9.(2) y is a multiple of 25.A.Statement (1) ALONE is sufficient,but statement (2) alone is not sufficient.B.Statement (

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If positive integer x is a multiple of 6 and positive integer y is a multiple of 14,is xy a multiple of 105?(1) x is a multiple of 9.(2) y is a multiple of 25.A.Statement (1) ALONE is sufficient,but statement (2) alone is not sufficient.B.Statement (

If positive integer x is a multiple of 6 and positive integer y is a multiple of 14,is xy a multiple of 105?(1) x is a multiple of 9.(2) y is a multiple of 25.A.Statement (1) ALONE is sufficient,but statement (2) alone is not sufficient.B.Statement (
If positive integer x is a multiple of 6 and positive integer y is a multiple of 14,is xy a multiple of 105?
(1) x is a multiple of 9.
(2) y is a multiple of 25.
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.
The product of the units digit,the tens digit,and the hundreds digit of the positive integer m is 96.What is the units digit of
(1) m is odd.
(2) The hundreds digit of m is 8.
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.
第一题答案是B,第二滴题答案是A,希望写出向出席步骤,

If positive integer x is a multiple of 6 and positive integer y is a multiple of 14,is xy a multiple of 105?(1) x is a multiple of 9.(2) y is a multiple of 25.A.Statement (1) ALONE is sufficient,but statement (2) alone is not sufficient.B.Statement (
x=6a=2*3*a,y=14b=2*7*b,a、b为正整数,
x*y=2*2*3*7*a*b
105=3*5*7
条件(1)并不能保证x*y是105的整数倍,条件(2)可以充分满足x*y是105的整数倍,
所以选B
设a、b、c为个位数,依题意有:
a*b*c=96=2*2*2*2*2*3,m=100a+10b+c,
当c是奇数时,m是奇数,当c是偶数时,m是偶数,
当a=8时,b*c=96/8=12=2*6=3*4,c可以是偶数,也可以是奇数,
结论,m可能是奇数也可能是偶数,取决于个位数的奇偶性.
条件(1)直接给出了m的奇偶性,可以肯定m是奇数,是充分的.
条件(2)不能肯定m的奇偶性,不充分.
所以选A.
英语的习惯与中文不同,比如第二题,中文会问判断数m的奇偶性时,下面哪个条件是充分条件,我们就很好理解.英语只问一句:What is 如果不看条件(1)、(2),天知道它要问m哪一方面的性质?
我觉得这两题考语言成分比考数学的成分要大得多.

的淡淡的恶毒的人反对反对是的