ghofran wrote:
3. Multiplication of the two digit numbers wx and cx, where w,x and c are
unique non-zero digits, the product is a three digit number. What is w+c-x?
(1) The three digits of the product are all the same and different from w c and x.
(2) x and w+c are odd numbers.
(1) wx+cx=aaa (111, 222, ... 999
=37*k) --> As x is the units digit in both numbers, a can be 1,4,6 or 9 (2,3,7 out because x^2 can not end with 2,3, or 7. 5 is out because in that case x also should be 5 and we know that x and a are distinct numbers).
1 is also out because 111=37*3 and we need 2 two digit numbers.
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Could you please explain for me what does unique non zero ?
>>> I feel that question is so silly but I had studied math in different language ( Arabic ) so I really have problem with many terms
second question is WHY you said aaa=37 k I could not undersand from where it comes
Thank you a lot I learn from here a lot of useful things .
Digits are ten digits 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. Non-zero digits are all of them except 0: 1, 2, 3, 4, 5, 6, 7, 8, and 9. Unique means that w,x and c are are all different from one another. Thus w, x and c are unique non-zero digits of the two digit numbers wx and cx means that w, x, and c are 1, 2, 3, 4, 5, 6, 7, 8, or 9.
As for 37k, each of the numbers 111, 222, ..., 999 are multiples of 37.
Hope it's clear.
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