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Is the three-digit number n less than 550?
(1) The product of the digits in n is 30
(2) The sum of the digits in n is 10.
Assume n= 100x+10y+z
(1) x*y*z = 30 ==> 1<=x,y,z<=9
x, y, z can be selected from 2, 3,5 or selected from 1, 5, 6
Maxium n= 651>550; miniun n=156 =>not sure
(2) x+y+z = 10 ==> 1<=x,y,z<=9 ==>Maxium n= 910; Minium n= 109 ==> not sure
For (1)+(2), the only possibility is that x, y, z is selected from 2, 3,5
So maxium n = 532 <550, the answer is n is definitely <550. |
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